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ProFlam-PN4131 is a non-halogenated flame retardant based on organic phosphinates for reinforced polyamide 6, polyamide 66 and high temperature polyamides. The product achieves its flame retardant effect through a combined gas phase and condensed phase mode of action. It can replace Exolit OP1400 which is launched by Clariant recently. Benefits: -Suited for applications in hot and humid environments -Outstanding thermal stability - widest processing window -UL 94V-0 rating down to 0.4 mm thickness -The flame retardant polyamide compounds exhibit very good physical and excellent electrical properties -Low material density -Good colorability -Good contrast in laser marking -Non-halogenated flame retardants with favorable environmental and health profile -Shows a high-potential for mechanical recycling while maintaining the flame retardancy and other properties. -Don't include Melamine Polyphosphate Applications: PN4131 was developed especially for use in polyamides. It is suited for polyamide 6 and 66 as well as polyphthalamides and other high temperature polyamides, e.g. PA 46, for both glass-fiber-reinforced and unreinforced grades. The flame retarded polyamide compounds exhibit very good physical and electrical properties. Dosage: In glass-fiber reinforced polyamide 6 or 6.6, a dosage of about 20 % (by wt.) of PN4131 is usually sufficient to obtain the UL 94 V-0 classification for electrical components (at 1.6 mm as well as 0.8 mm and 0.4 mm thickness). In semi-aromatic polyamides the dosage can be reduced to approx. 15%. Subject to the polymer grade, processing conditions and glass- fibre reinforcement the dosage of the flame retardant may vary.

The most practical PVC processing aid Its structure is between the two structures, such as ABS. Specific varieties of PVC resin are: (1) Chlorinated polyethylene (CPE): A powdery product that uses HDPE to suspend chlorination in the water phase. As the degree of chlorination increases, the original crystalline HDPE gradually becomes an amorphous elastomer. CPE used as a toughening agent generally contains 25%-45% Cl. In the production of PVC pipes and profiles, most factories use CPE. The amount added is generally 5-15 parts. (2) ACR: It is the best impact modifier developed in recent years, which can increase the impact strength of materials dozens of times. It is suitable for impact modification of PVC plastic products used outdoors. It is used in PVC plastic door and window profiles. It has the characteristics of good processing performance, smooth surface, good aging resistance, and high weld angle strength, but the price is about 1/3 higher than CPE. (3) MBS: The solubility parameter is between 9.4 and 9.5, which is close to that of PVC, so it has better compatibility with PVC. After adding PVC, it can be made into a transparent product. Generally, adding 10-17 parts to PVC can increase the impact strength of PVC by 6-15 times, but when the amount of MBS added is 30 parts larger, the impact strength of PVC will decrease instead. The price of MBS is relatively high, and it is often used together with other additives such as EAV, CPE, and SBS. MBS has poor heat resistance and poor weather resistance, so it is not suitable for long-term outdoor use, and generally does not need to be used as plastic door and window profiles. (4) ABS: It is mainly used as engineering plastics, and also used as PVC impact modification, and the effect of low temperature impact modification is also very good. When the amount of ABS added reaches 50 parts, the impact strength of PVC can be equivalent to that of pure ABS. The amount of ABS added is generally 5-20 parts. ABS has poor weather resistance and is not suitable for long-term outdoor use products. Generally, it is not used as an impact modifier for the production of plastic door and window profiles. (5) EVA: Moreover, the refractive index of EVA and PVC is different, and it is difficult to obtain transparent products. EVA is often used together with other impact-resistant resins. The amount of EVA added is less than 10 parts.

PVC processing requires the use of many additives, thanks to which it is possible to obtain products for different purposes and with different levels of flexibility.PVC is very easily modified and therefore its properties can be freely customized to very different requirements depending on the intended use.Modification is accomplished through the appropriate selection of PVC blend components.A variety of stabilizers, plasticizers, impact and flow modifiers, fillers, and other additives are used to produce PVC plastics. A feature that distinguishes PVC from other thermoplastic materials is the ability to modify its physical and mechanical properties via plasticizing, which has long been a widely used means of modification.Plasticizers are added to PVC in order to achieve the required level of flexibility of the end product.Their main task is to decrease the Tg (the glass transition temperature) of the PVC, which in turn leads to a lowering of the gelling and moulding temperature during processing.This also leads to a permanent improvement of the properties of the polymer, including itsflexibility, impact resistance and resistance to low temperatures.Plasticizers, which this article provides a general overview of, are one of the wide array of additives used in PVC processing. They will be discussed in more detail in subsequent articles.Plasticizers can be classified based on different criteria, such as: – process characteristics (high-temperature, low-temperature plasticizers), – type of chemical (phthalates, phosphates, polyesters etc.), – molecular weight (monomeric, polymeric). The most common plasticizer groups include: phthalic acid esters (DEHP, DIDP, DINP) (DTDP), adipic acid esters (DINA), (DIDA) – added to products used in low temperatures, sebacic acid esters (DBS), (DOS) – provide PVC plastificates with resistance to low temperatures, phosphate softeners-used in PVC plastificates with reduced flammability, polymeric softeners-characterized by low migration and resistance to extraction, trimelliates – used in PVC plastificates resistant to high temperatures. phthalate-free – introduced in response to restrictions placed on phthalate plasticizers (e.g.Grupa Azoty – Oxoviflex® – DEHT :used in the production of carpets, vinyl wallpaper, flexible pipes (plumbing), cable tubing and conduits, artificial leather, packagings and plastic films, PVC coatings, products for children) There is also another division of plasticizers into primary and secondary type, which is based on their solvation properties and degree of compatibility with PVC. These will be described in subsequent articles.In accordance with the requirements of Directive 2005/84/EC relating to the classification, packaging and labelling of dangerous substances, it is being recommended that six phthalates be eliminated (BBP, DBP, DEHP, DINP, DIDP, DNOP).This subject and other information about phthalates and plasticizers are going to be discussed in the articles to come. Due to PVC degradation that occurs during processing, PVC needs to be mixed with stabilisers in order to prevent its destruction. Stabilisers also help PVC to maintain its properties in the course of its lifetime.Poly(vinyl chloride) is very sensitive to elevated temperatures and light, and undergoes significant destruction when exposed to these factors.In order to prevent the thermal deterioration of PVC during processing and light-induced degradation of the finished product, chemical compounds with a stabilising effect are used. Stabilisers consist of a wide variety of chemical substances. They are added to PVC alone or in multi-component blends demonstrating a synergistic effect. The latter are prepared in a dust-free form as so-called [one-pack" stabilisers. Their composition is adapted to the processing conditions and to the intended use of the product. At the moment, the main stabilisers used with PVC include: blends of metal-based stabilisers – Ca, Ca-Zn, Zn-Mg, Ba-Ca and Ba-Zn-Ca (generally stearates).They are suitable for stabilization of non-plasticized, semi-hard, plasticized PVCs and plastisols.Zn-Mg stabilisers are used in hard and flexible blends in place of obsolete Ba-Cd stabilisers, whereas Ba-Zn stabilisers are a substitute of cadmium-based stabilisers. In turn, Ba-Zn and Ca-Zn stabilisers are used with softened PVCs as a substitute for lead stabilisers.Ca-Zn stabilisers are used primarily for products made of plasticized poly(vinyl chloride) (PVC-P), intended for use in products which come into contact with food and in those used by children. organotin stabilizers – i.e. butyl, octyl and methyl tin mercaptides, butyl and octyl tin carboxylates and octyl tin maleates.PVC products which incorporate these stabilisers are characterised by a high level of transparency.They are especially suitable for the stabilisation of hard PVC processed via calendering, extrusion and injection moulding. organic stabilisers – including organotin compounds, organic phosphites, epoxy compounds, aminocrotonates and a-phenylindoles. This part of the article will present 2 of the largest groups of additives, while part II will deal with lubricants, impact modifiers, fillers and dyes used in the processing of PVC.

Flame retardancy process can be characterized either in gas phase, by investigating present pyrolysis species, or in solid phase, by studying the morphology and composition of the char layer. There are numerous macro and micro fire characterization methods. Limiting oxygen index (LOI), UL-94, cone calorimetry, microscale calorimetry, and thermogravimetric analysis (TGA) are of the most common fire characterization methods. LOI is one of the primary methods that has been used for many years to investigate the relative flammability of materials. Material with LOI less than 21% can burn easily whereas materials with LOI greater than 21% exhibit reduced flammability after removal from ignition source. LOI requires a cost-effective setup and small sample size. However, due to the high oxygen index simulation and small scale input heat, it is not very suitable for determining the real extent of fire performance. UL-94 tests have been considered for measuring burning rate and characteristics of plastics. UL94 vertical test is widely used for determination of ignitability and flame spread rate of plastic materials. In this test, the specimen is burnt using specific flame conditions for a certain time period. The time required for the fire to be extinguished (after-flame removal) is an indication of fire retardancy properties of the specimen. As one of the most important fire characterization methods for polymeric materials, cone calorimetry measures the reducing oxygen concentration in the combustion gasses of a specimen subjected to a given heat flux. After exposing the sample to a conical radiant electrical heater, the combustion is triggered by an electric spark. Variety of data, such as, heat release rate (HRR) as a function of time, peak of heat release rate (pHRR), total heat release rate (THR), and mass loss rate (MLR) can be reported by this test. Microscale calorimetry test provides a rapid, cost-effective method for academic and industrial polymer research. Studies suggest the potential of this method for quantitative determination of full-scale fire performance for milligram samples. Samples are thermally decomposed at a constant heating rate. Then, combustion products from solid state pyrolysis are removed using nitrogen and then mixed with excess oxygen to ensure complete combustion. The oxygen exhaustion is measured by analyzing the remaining oxygen/nitrogen mixture after the elimination of combustion volatiles from the gas stream. The heat release rate and other flammability parameters, such as, heat release capacity and char yield are among the outcomes of microscale calorimetry. TGA measures the changes in weight of materials as a function of temperature based on ASTM E1131 and ISO 11358 standards. Weight loss at onset temperature (Tonset) and percentage of the weight that remains at the end of the heating process (including mass of char residue) are obtained by TGA. Materials with higher Tonset produce less fuel for the combustion and therefore have better flame retardancy properties. Novista Group supplies DBDPE, BDDP, FR245, TTBP,SR130 to global market.

According to their specific mechanisms, fire retardants interrupt polymer pyrolysis in one or more steps. Three of the most common flame retardancy mechanisms are described in previous studies. Gas phase inhibition mechanism, where the FRs react with the polymer under combustion in the gas phase with hydroxyl or oxygen agents at the molecular level and extinguish the combustion. Halogenated and phosphorous FRs are common in this category. Hydrated minerals (halogen free) decompose in an endothermic reaction when exposed to fire, using a cooling mechanism. They release water molecules that cool down the combustion environment of polymers. Char forming polymers (e.g. cellulose or carbon family FRs) react to combustion in a solid phase. these FRs crosslink to the polymer matrix in elevated temperatures and create a barrier layer that hinders the heat transfer and release of additional gasses. They react to form a porous carbonaceous 3D-char layer that insulate the polymer surface and slow down the pyrolysis. Intumescent FRs, such as, melamine compounds and phosphorous compounds are from this category. Novista Group supplies equivalent of FP-2100JC, FP-2200S, FP-2500S, Exolit OP1230, OP930, OP1312, OP1314 to global market.

In order to meet fire safety requirements and diminish fire hazards, different solutions have been developed. Various chemical and physical strategies have evolved to prevent polymers from burning or to lower the heat release amount. Recently, flame retardants (FRs) have been widely recognized as fire safety tools capable of lowering the number of fire injuries and death. The term flame retardant refers to a diverse group of chemicals that are added to synthesis materials, such as, plastics to prevent or slow down the combustion process. Adding flame retardants to polymers, fibers, and papers are an expanding trend that can protect the final product from burning. Therefore, it is clear that flame retardants are an important part of polymer composite formulations. Role of FRs is significant for those cases that polymers have a high chance of being exposed to the ignition source (like in electronics and electrical applications), and those where polymers can ignite and spread fire quickly (like in residential and industrial buildings, limiting evacuation, and transportation). Novista Group supplies APP, MCA, aluminium hydroxide,magnesium hydroxide to global market.

A PVC foaming regulator is actually an acrylic resin based processing aid that has all the basic functions of a PVC processing aid, with the difference compared to conventional processing aids. PVC foaming regulator has higher molecular weight and higher viscosity As a common product, PVC foaming regulator, how much do you know about its basic knowledge? Let's take a look at the basic knowledge of PVC foaming regulators. 1. The chemical composition of PVC foaming regulator. A PVC foaming regulator is actually an acrylic resin based processing aid that has all the basic functions of a PVC processing aid, with the difference compared to conventional processing aids. PVC foaming regulators have higher molecular weight and higher viscosity. 2. The main function of foaming regulator in PVC foam products. Promote the plasticization of PVC, and improve the melt strength of PVC foam materials, prevent bubble coalescence, and obtain a uniform foamed product. Preventing insufficient melt strength results in foam sheet foaming, longitudinal pimples and ensuring good melt flow for good product appearance. 3. A simple and effective method for checking melt strength. To determine whether the melt strength is insufficient, the direct method is to wrap the fingers in the middle roll of the sheet and press the three rolls back, the melt strength is good, and the elasticity can be felt when pressing. If the press is hard to bounce back, it indicates poor melt strength.

Choice of PVC impact modifier The selection of impact modifiers should pay attention to the following aspects: 1. The compatibility with PVC resin should be moderate. If the compatibility is too large, the two are completely mixed at the molecular level. The impact modifier may play the role of plasticizer, which is closely attached to the PVC molecules, causing impact The force acts directly on the PVC chain and cannot improve the impact resistance. On the other hand, if the compatibility between the two is too small, the uniform dispersion cannot be achieved, the adhesion to PVC is lost, and the impact force cannot be absorbed. 2. The glass transition temperature should be low, which can improve the impact resistance of PVC at low temperature. 3. The molecular weight should be high, and if necessary, it is best to lightly cross-link to improve the reinforcing effect. 4. It has no obvious influence on the performance and physical properties of PVC. 5. The weather resistance should be good, and the mold release expansion should be small. 6. Good processability for blending with PVC. 7, heat resistance (deformation resistance, thermal stability) is better. 8. Economical .

Optical brightener (OB) and Optical Brightener -1(OB-1) are brightening agents often confused with each other. Both are used for brightening but on different types of materials. Therefore, it is essential to understand the details and differences between them before selecting. What is Optical Brightener(OB)? Optical Brighteners have a wide range of applications; fabric whitening is one. Materials such as plastics have a certain level of yellowness that gives them a dull finish. To increase brightness to the products, OB is added to the plastics. A similar application takes place for the fabric. Other colorants are used along with the Optical Brightener to derive the required color and shade in the materials. Optical Brighteners are easily used in plastics as they have a high melting point which helps them easily mix with the molten plastic. What is OB-1? OB-1 has a similar effect but with different chemical formulas and applications. It is also used in textiles and plastics to increase the whiteness of the product. The final whiteness derived using OB-1 has a light reddish-blue effect. What Product Uses Optical Brightener OB, Which Product Is More Suitable For Optical Brightener OB-1? One of the main differentiators can be the products on which OB and OB-1 can be used. This is decided based on the melting point. The melting point of OB is lower than OB-1. However, the latter has a high melting point of about 360 degrees. Therefore, it is unsuitable for high-temperature products, and OB can be used in such cases. On the other hand, OB-1 can be used in materials that require high-temperature processing. Differences Between Optical Brightener OB And Optical Brightener OB-1 vary in different aspects. Here are some of the fundamental differences: 1. Melting point The melting point of the Optical Brightener is 200 degrees which is lower than the Optical Brightener-1, which is 360 degrees. This largely determines the application of both the Optical Brighteners. 2. Dispersion Dispersion mainly defines the stability of the application. A product with good dispersibility will have a long-lasting whitening effect, and the product`s yellowness will be very slow. OB is known to have better dispersibility and stability than OB-1. This is why OB is recommended to be used in ink coatings as the OB is not prone to the yellowing that might start early with OB-1. 3. Price Price becomes a decisive point in making decisions on selection when the Optical Brightener is used on a larger scale. OB is way costlier than OB-1. Most manufacturers choose the latter over the former as it`s cheap. However, specific applications such as special ink coatings need OB to manufacture. Therefore, innovations and R&D activities are finding a more affordable and more effective alternative to OB.

Optical brightening agents (OBAs) / Optical brightener, also known as fluorescent brightening agents (FBAs), are chemical compounds that give whitening effect to fabric. They do this by absorbing light in the ultraviolet and violet regionand re-emit the light in the blue region. This blue light reduces the yellow colour of the substrate and give a brightened look. Unlike bleaching, it doesn`t leave ayellowish tinge and gives a much pleasing whiter-than-white appearance. Such a property sets optical brightening agents apart and makes it a much coveted thing in industries such as Textiles, Plastics, Paper, and Cosmetics. Types of Optical Brightening Agents Based on the number of sulphonic groups, brightening agents can be categorised into three main types. 1) Disulfonated Optical Brightening Agents These optical brightenets consist of two sulphonic groups. These agents are hydrophobic in nature because of their chemical composition. In simpler words, the solubility of these OBAs is quite low. Typically, they`re used in wet end. 2) Tetrasulfonated types As the name suggests, these brighteners are made by four sulphonic groups. This type of brightening agents exhibit medium affinity and good solubility. Therefore, they`re an ideal solution in wet end as well as in dry end. These OBAs are most commonly used OBA type used in paper and paper board. 3) Hexasulfonated OBAs Hexasulfonated OBAs are the kind of OBAs that are made of six sulphonic groups. As a result, these OBAs display a remarkable solubility and they`re used in dry end coating. They`re mostly used in areas where high brightness is required.

Chemical properties: Titanium dioxide has extremely stable chemical properties and is a kind of acidic amphoteric oxide. It hardly reacts with other elements and compounds at normal temperature, and has no effect on oxygen, ammonia, nitrogen, hydrogen sulfide, carbon dioxide and sulfur dioxide. It is insoluble in water, fat, dilute acid, inorganic acid and alkali, and only soluble in hydrofluoric acid. However, under the action of light, titanium dioxide can undergo continuous oxidation-reduction reaction and has photochemical activity. This kind of photochemical activity is particularly evident in anatase titanium dioxide under ultraviolet irradiation. This property makes titanium dioxide both a photosensitive oxidation catalyst for some inorganic compounds and a photosensitive reduction catalyst for some organic compounds. Emergency treatment: isolate the leakage contaminated area and restrict access. It is recommended that emergency treatment personnel wear dust masks (full masks) and general work clothes. Avoid raising dust, sweep it carefully, place it in a bag and transfer it to a safe place. If there is a large amount of leakage, cover it with plastic cloth and canvas. Collect and recycle or transport to the waste treatment site for disposal. Titanium dioxide (or titanium dioxide) is widely used in various structural surface coatings, paper coatings and fillers, plastics and elastomers. Other applications include ceramics, glass, catalysts, coated fabrics, printing inks, roof paving and flux. According to statistics, the global demand for titanium dioxide in 2006 reached 4.6 million tons, of which the coating industry accounted for 58%, the plastics industry 23%, papermaking 10% and others 9%. Titanium dioxide can be made from ilmenite, rutile and titanium slag. There are two kinds of titanium dioxide production processes: sulfate process and chloride process. The sulfate process is simpler than the chloride process. Minerals with low grade and relatively cheap can be used. Today, about 47% of the world`s production capacity is sulfate process, and 53% is chloride process. (THE END)

Bromine is used as a flame retardant, in addition to mercury removal, air purification and other fields. With the wide application of polymer materials such as plastics in household environments, public places and vehicles, flame retardants have increasingly become a must-added fire retardant. Currently, flame retardants are mainly used in four fields: transportation, electronic and electrical equipment, furniture, and buildings and construction materials. There are more than 200 kinds of flame retardant family products, which can be divided into bromine-based, phosphorus-based, nitrogen-based, silicon-based and inorganic flame retardants according to different elements. There is also an inevitability to this diversity, as the materials and products that are to be fire resistant vary widely in properties, composition and even application. Some flame retardants may be very suitable for some specific applications, but not in other areas. That is, there is no one flame retardant, and different solutions must be selected according to different applications. Material engineers will select suitable flame retardants according to the structure and properties of materials. For example, 80% to 90% of printed circuit boards use brominated flame retardants. Brominated flame retardants are very efficient and can capture free radicals in the combustion chain reaction, terminating or slowing down the chain reaction, thus playing a role in flame retardant. In addition, the cost-effectiveness of brominated flame retardants ranks in the forefront of various existing flame retardants, and has little impact on the performance of the substrate. It is suitable for flame retardant various plastics, rubbers, fibers and coatings. Novista Group supplies DBDPE, BDDP, FR245, TTBP,SR130 to global market.

Flame retardants are chemicals added to materials to interfere with combustion. This disturbance is usually to achieve some desired refractory properties - slow ignition, reduce flame spread, etc. Widely used in plastic, wood and textile fire protection. Phosphorus flame retardants (including organic phosphorus and inorganic phosphorus) can carbonize the combustion material to achieve a flame retardant effect. This flame retardant effect mainly plays a role in the solid phase. In order to impart basic flame retardant properties to plastics, inorganic fillers (aluminum hydroxide, magnesium hydroxide) have also been used, which can release water molecules by thermal decomposition. Novista Group supplies equivalent of FP-2100JC, FP-2200S, FP-2500S, Exolit OP1230, OP930, OP1312, OP1314 to global market.

In recent years, with the increase in the output of plastic products and the improvement of safety standards, flame retardant materials are more widely used. Generally speaking, flame retardant materials can be divided into organic flame retardant materials and inorganic flame retardant materials. The organic flame retardant has good flame retardant effect and the addition amount is relatively small. However, organic flame retardants have the drawbacks of generating large amounts of smoke and releasing toxic gases during combustion. Inorganic flame retardants have the advantages of non-toxic, smoke-free, non-volatile and cheap, but the amount of addition is relatively large. 1. Halogen flame retardant Halogen flame retardants are not only large in output, but also widely used. The material added with the flame retardant can release hydrogen halide and obtain free radicals during the combustion process, thereby preventing the transfer of the combustion chain, and then generating free radicals with low activity to slow down the combustion. Halogen flame retardants are generally used in thermoplastic materials and thermosetting materials. They not only have good compatibility with polymer materials, but also are easy to use. Therefore, they are welcomed by the market and are widely used in automobile, packaging, textile and other industries. 2. Phosphorus flame retardant Inorganic phosphorus flame retardants mainly include phosphates, red phosphorus, etc. Red phosphorus is widely used. Red phosphorus is a good flame retardant, but in practical applications, red phosphorus flame retardant materials are easy to oxidize and release harmful Highly toxic gas, and dust generated by combustion can easily lead to explosion, and there is a certain danger in resin mixing and molding processing. Therefore, phosphorus-based flame retardant materials are subject to certain restrictions on their use. The improved red phosphorus flame retardant is added with metal hydroxide, which solves the toxicity problem of polymer materials to a certain extent. 3. Nitrogen flame retardant Commonly used varieties are melamine, melamine cyanurate (MCA), etc., often need to add synergist, nitrogen/phosphorus is a commonly used synergistic flame retardant system, mainly used in PA, PU, PO, PET, PS, PVC and other resins. Melamine cyanurate is a nitrogen-containing halogen-free environment-friendly flame retardant, especially suitable for unfilled PA6 and PA66, available in powder and granular forms. When the flame-retardant polyamide foam of this product is burned, the formed carbon foam layer protects the polymer and insulates heat and oxygen. 4. Metal oxide flame retardant Metal oxide flame retardants mainly add inorganic elements with intrinsic flame retardancy to the base material to be flame retardant in the form of simple substances or compounds, fully mix with high polymers in a physically dispersed state, and pass through the gas phase or condensed phase. Chemical or physical changes act as flame retardants. Aluminum hydroxide is the most popular flame retardant for inorganic hydroxides. It is mainly used for artificial rubber, thermosetting resin and thermoplastic plastics whose processing temperature is below 200℃. Aluminum hydroxide flame retardant plastics are less smoky in flames which is a distinct advantage. Magnesium hydroxide is an inorganic flame retardant with better thermal stability. It is still stable when it exceeds 300 °C. It is widely used in many artificial rubbers, resins, including engineering plastics and other resins processed at high temperatures. In the polymer system, it plays the role of flame retardant and smoke elimination. When used in combination with ATH, it complements each other, and its flame retardant effect is better than that used alone. Novista Group supplies APP, MCA, aluminium hydroxide,magnesium hydroxide to global market.

Crystal structure: Titanium dioxide has three crystalline forms in nature: rutile, anatase and plate titanium. Plate titanium type belongs to the orthorhombic system, which is an unstable crystal type. It is transformed into rutile type at above 650 ℃, so it has no practical value in industry. Anatase is stable at room temperature, but it should be transformed into rutile at high temperature. The conversion strength depends on the manufacturing method and whether inhibition or accelerator is added in the calcination process. It is generally believed that there is almost no crystal transformation below 165 ℃, and the transformation is fast when it exceeds 730 ℃. Rutile is the most stable crystalline form of titanium dioxide, with dense structure. Compared with anatase, rutile has higher hardness, density, dielectric constant and refractive index. Rutile and anatase belong to tetragonal system, but have different lattice, so the X-ray images are also different. The diffraction angle of anatase titanium dioxide is 25.5 °, and that of rutile is 27.5 °. Rutile crystal is slender and prismatic, usually twin; However, anatase generally approximates regular octahedron. Compared with anatase, rutile type is composed of two titanium dioxide molecules in its unit lattice, while anatase type is composed of four titanium dioxide molecules, so its unit lattice is small and compact, so it has greater stability and relative density, so it has higher refractive index, dielectric constant and lower thermal conductivity. Among the three isomers of titanium dioxide, only rutile is the most stable, and only rutile can be obtained by thermal conversion. Natural brookite can be transformed into rutile at 650 ℃, and anatase can also be transformed into rutile at 915 ℃.

6) Hygroscopicity: Although titanium dioxide has hydrophilicity, but its hygroscopicity not very strong, and rutile type is smaller than anatase type. The hygroscopicity of titanium dioxide is related to its surface area. The large surface area and high hygroscopicity are also related to surface treatment and properties. 7) Thermal stability: Titanium dioxide is a material with good thermal stability. 8) Grain size: The particle size distribution of titanium dioxide is a comprehensive index, which seriously affects the performance of titanium dioxide pigment and product application performance. Therefore, the discussion on hiding power and dispersion can be directly analyzed from the particle size distribution. The factors affecting the particle size distribution of titanium dioxide powder are complex. First, the original particle size of hydrolysis is controlled and adjusted to make the original particle size within a certain range. The second is calcination temperature. During the calcination of metatitanic acid, the particles go through a crystal transformation period and growth period. Control the appropriate temperature to make the growth particles within a certain range. Finally, is crushed. Usually, remoulding of Raymond mill and the adjustment of analyzer speed used to control the crushing quality. At the same time, other crushing equipment can be used, such as universal mill, air flow mill and hammer mill.

Titanium dioxide (TiO2), an important inorganic chemical pigment, is mainly composed of titanium dioxide. The production process of titanium dioxide includes sulfuric acid process and chlorination process. It is widely used in coating, ink, paper making, plastic rubber, chemical fiber, ceramics and other industries. TiO2 physical characteristics: 1) Titanium dioxide relative density Among commonly used white pigments, titanium dioxide has the lowest relative density. Among the white pigments of the same quality, titanium dioxide has the largest surface area and the highest pigment volume. 2) Titanium dioxide melting point and boiling point: Because anatase can change into rutile at high temperature, the melting point and boiling point of anatase titanium dioxide do not actually exist. Only rutile titanium dioxide has melting point and boiling point. The melting point of rutile titanium dioxide is 1850 ℃, the melting point in air is (1830 ± 15) ℃, and the melting point in oxygen enrichment is 1879 ℃. Melting point is related to the purity of titanium dioxide. The boiling point of rutile titanium dioxide is (3200 ± 300) ℃, and titanium dioxide is slightly volatile at this high temperature. 3) Dielectric constant: Titanium dioxide has excellent electrical properties because of its high dielectric constant. When determining some physical properties of titanium dioxide, the crystallization direction of titanium dioxide crystal should be considered. The dielectric constant of anatase titanium dioxide is relatively low, only 48. 4) Conductivity: Titanium dioxide has semiconductor properties. Its conductivity increases rapidly with the increase of temperature, and it is also very sensitive to hypoxia. The dielectric constant and semiconductor properties of rutile titanium dioxide are very important to the electronic industry, which can be used to produce electronic components such as ceramic capacitors. 5) Hardness: According to Mohs hardness scale, rutile titanium dioxide is 6 ~ 6.5 and anatase titanium dioxide is 5.5 ~ 6.0. Therefore, anatase titanium is used in chemical fiber matting to avoid wear of spinneret holes. (To be continued...)

As the name suggests, flame retardants are additives used to prevent materials from being ignited and inhibit the spread of fire. They are mainly designed for the flame retardant of polymer materials. Generally speaking, flame retardants mainly play the role of endothermic, covering, chain inhibition and non-combustible gas suffocation to achieve the flame retardant effect. Materials processed with flame retardants can effectively prevent and delay the spread of flames when attacked by external fire sources. Flame retardants are divided into two categories: organic flame retardants and inorganic flame retardants. Among them, organic flame retardants include organic phosphorus flame retardants and organic halogen flame retardants. The representative products of organic halogen flame retardants It is an organic brominated flame retardant; inorganic flame retardants are mainly various metal oxides, There are big differences in performance, flame retardant efficiency and environmental protection among the three major types of flame retardants: organic halogen, organic phosphorus and inorganic, and their application fields are also different. Various flame retardant properties Compared with organic halogen flame retardants, organophosphorus flame retardants are characterized by low toxicity, less smoke, low corrosion, good compatibility with materials, and dual functions of flame retardant and plasticization. In developed countries and regions such as Europe, America, Japan and South Korea, the market share of organophosphorus flame retardants is gradually expanding, and there is a clear trend to replace organic halogen flame retardants. In China, the development of organophosphorus flame retardants started late, and the market prospect is broad. In the field of polyurethane materials, polyurethane soft foam flame retardants are mostly used in daily life, including sofas, carpets, seat cushions, etc., and downstream customers are relatively scattered; polyurethane rigid foam flame retardants are widely used in industrial fields, such as building insulation materials , refrigerators, pipeline insulation materials, etc., customers are concentrated in Europe and the United States; the main application fields of polyurethane thermoplastic elastomer flame retardants are transportation, civil construction, footwear, fabrics and other materials. Engineering plastic flame retardants are mainly used to make polycarbonate, nylon, polyester and other materials. Among them, carbonate materials are widely used in televisions, computers and mobile phones. Novista Group supplies DBDPE, BDDP, FR245, TTBP,SR130 to global market.

1. It produces a gas that smothers the flame. For example, antimony trioxide reacts with HCl from combustion in PVC to form a smoldering gas, namely antimony nitrogen oxide. 2. It can absorb the heat produced during combustion and cool down the combustion rate. For example, aluminum hydroxide contains up to 34% of chemically associating water in its molecules, which remains stable at the processing temperature of most plastics, but begins to decompose when it exceeds 200 ℃ and releases water vapor. And every gram of aluminum hydroxide decomposition, to absorb 36 kcal heat. 3. It provides a coating insulated from oxygen. For example, the phosphide produced by the combustion of phosphate flame retardant is an oxygen barrier coating. 4. It can form free radicals which can react with plastics and act as flame retardant. The combustion properties of the products from their reaction with plastics are very poor. Novista Group supplies equivalent of FP-2100JC, FP-2200S, FP-2500S, Exolit OP1230, OP930, OP1312, OP1314 to global market.

Flame retardant is a kind of additive which can prevent the ignition of polymer materials or inhibit the flame propagation. Common and important flame retardants are compounds of phosphorus, bromine, chlorine, antimony and aluminum. Flame retardants can be divided into additive type and reactive type. The additive flame retardants mainly include phosphate ester, halogenated hydrocarbon and antimony oxide. They are mixed into the composite during the processing of composite materials. They are easy to use and have a wide range of applications, but they have an impact on the properties of the composite materials. Reactive flame retardant is a kind of monomer material added into the polymerization system in the process of polymer preparation, which is compounded to the polymer molecular chain through chemical reaction. Therefore, it has little effect on the properties of the composite and has a long flame retardancy. Reactive flame retardants mainly include phosphorus containing polyols and halogenated anhydrides. The flame retardants used in composite materials should have the following properties: 1) high flame retardant efficiency, which can give the composite good self extinguishing or flame retardant properties; 2) it has good compatibility with the composite materials and is easy to disperse; 3) it has a suitable decomposition temperature, that is, it does not decompose at the processing temperature of the composite, but can decompose rapidly when the composite is decomposed by heating The results show that the flame retardant effect is not toxic or low toxic, odorless and pollution-free, and no toxic gas is produced in the process of flame retardant; 4) when used with composite materials, the mechanical properties, electrical properties, weather resistance and thermal deformation temperature of the composite materials will not be reduced; 5) good durability, which can be retained in the composite products for a long time to play its flame retardant role; and (7) the source is wide and the price is low. (1) Brominated flame retardants Brominated flame retardants include aliphatic, alicyclic, aromatic and aromatic aliphatic brominated compounds. This kind of flame retardant has high flame retardant efficiency, and its flame retardant effect is twice as much as that of chlorodi flame retardant. The relative amount of brominated flame retardant has little effect on the mechanical properties of the composite, and can significantly reduce the content of hydrogen halide in the gas. Moreover, this kind of flame retardant has good compatibility with the matrix resin Under harsh conditions, there is no ejection phenomenon. (2) Chlorine based flame retardants are still widely used because of their low cost. Chlorinated paraffin with high chlorine content is an important flame retardant in industry. Due to its poor thermal stability, it is only suitable for composites with processing temperature lower than 200 ℃. Chlorinated aliphatic hydrocarbons and tetrachloro phthalic anhydride have high thermal stability and are commonly used as flame retardants for unsaturated resins. (3) Phosphorus based flame retardants and organic phosphates are additive flame retardants. Metaphosphoric acid produced by these flame retardants can form a stable polymer and cover the surface of composite materials to isolate oxygen and combustible materials. Their flame retardant effect is better than that of bromide. To achieve the same flame retardant effect, the amount of bromide is 4-7 times of that of phosphide. This kind of flame retardants mainly include phosphonate ester, halogenated phosphate ester and halogenated phosphorus, etc., which are widely used in epoxy resin, phenolic resin, polyester, polycarbonate, polyurethane, polyvinyl chloride, polyethylene, polypropylene, ABS, etc. (4) Inorganic flame retardant inorganic flame retardant is a kind of flame retardant according to its chemical structure, including antimony oxide, aluminum hydroxide, magnesium hydroxide and zinc borate. Novista Group supplies APP, MCA, aluminium hydroxide,magnesium hydroxide to global market.