Overview of rubber processing aids at home and abroad
Rubber Processing Aids
Abstract: What are rubber processing aids? How are they categorized? Problems that exist at present
Search term: rubber auxiliaries, rubber processing aids.
With the rapid development of the domestic rubber industry, especially the reform and opening up over the past 30 years, a variety of social manuals about rubber processing and rubber auxiliaries emerged in large quantities, including rubber antioxidants and vulcanization accelerators are introduced in more detail, but the processing aids to talk about the more simple and chaotic, the concept of ambiguity, which is undoubtedly the development of our industry is a lack of, and is now trying to summarize and categorize, some of the superficial introduction for the Peers for reference.
1 Overview:
Rubber processing aids is a component of rubber chemicals, it is with the production of radial tires and the birth of a 50-year history in foreign countries, the number and varieties are still increasing year by year, the domestic emergence of a relatively slow, it is only in the last 10 years, but the development of a very fast, the birth of the rubber chemicals has changed the composition of rubber chemicals in the last century, the 50s of the composition of 90% of the rubber chemicals for the composition of the rubber antioxidant and rubber vulcanization Promoter, and today has been reduced to 74%, of which antioxidants and accelerators accounted for 34%, the rest for a variety of professional additives.
(1) rubber processing aids originally referred to:
Add a very small amount to improve processing performance, but does not significantly affect the physical properties of the product is known as rubber processing aids, but now has appeared both to improve the physical properties of rubber, but also to improve the processing performance of the additives.
Rubber processing aids in the future direction of development is: In addition to the basic properties of rubber and rubber, rubber and additives dispersion and uniformity should be good, but also should be efficient, low energy consumption, pollution-free and multi-functional.
Due to the rapid development of the domestic rubber industry, the rapid development of domestic processing aids products in addition, but also caused a number of foreign-funded processing aids enterprises have boarded the market in China, which has:
In addition there are many professional suppliers and service providers of processing aids to our Chinese tire factories and rubber factories to introduce processing aids, of which the famous ones are:
2 Classification of processing aids:
1 Dispersant .
Role: Improve the dispersion of carbon black and other powders in the rubber, prevent sticky rollers, reduce scorching and shorten processing time. It also has the ability to improve the fluidity of the rubber and has a plasticizing effect.
Composition: polymerized products of polymer fatty acid esters or mixtures with metal soaps.
2.2 Homogenizers
Role: To solve the different polarity and different viscosity polymer blending. Currently in the different polarity of the raw rubber and used in the formulation and butyl lining layer of the rubber is widely used, in addition to plasticizing, viscosity and lubrication functions, can improve the processing of the rubber compound, reduce energy consumption, such as to improve the speed of tread adhesive compression out of the rubber to improve the viscosity of the rubber compound and the physical properties of the material, is a very effective class of processing aids.
Composition: A mixture of low molecular resins of different polarities. Manufacturers generally do not disclose the exact composition and ratio of their products. Its production process is generally obtained through the thermal polymerization of raw materials or intermediates; can also be several resins according to the percentage of physical methods mixed into one. Or it can be obtained by granulation.
Typical domestic commodities
According to preliminary statistics, in 2006, only the tire industry’s demand for homogeneous agent reached about 4000 tons, according to the domestic sales price of the product calculation, at least should be 140 million yuan of market prospects.
2.3 Plasticizer
Role: in plasticizing to improve the flexibility of polymer or tensile properties of processing aids. According to its mechanism of action can be divided into physical plasticizers and chemical plasticizers two categories. It is customary to refer to chemical plasticizers as plasticizers.
2.31 Physical plasticizers: its addition can reduce the viscosity of the mixing rubber, increase the plasticity of the rubber, and can improve the dispersion of carbon black and other agents, improve the physical properties of vulcanized rubber. Chemical plasticizers are added in the plasticizing of raw rubber, not only has the effect of improving the plasticizing effect, shortening the plasticizing time, saving energy, but also has a low dosage, strong plasticizing power.
Composition: unsaturated or saturated fatty acids, fatty acid esters or their zinc soap is currently the most widely used physical plasticizer.
Typical foreign commodities: Struktol A60/A61 in the United States.
2.3.2 Chemical plasticizers: also known as plasticizer.
Composition: It is added to enhance the plasticizing effect of raw rubber through chemical action, greatly shorten the plasticizing time, so that both energy saving and improve the mechanical efficiency. According to the structure can be divided into:
a. Pentachlorothiophenol products
b. Aryl disulfides
C . C. Organometallic complexes
Among the above three types of products, Pentachlorothiophenol products have been banned in foreign countries and Europe because of its toxicity, but it is still used in large quantities in China because of its cheap price; Aryl disulfide is a famous plastisol agent in foreign countries, which is non-toxic and has good effect of plastisol, and Haicheng Chemical Auxiliaries Factory in China is the leader of this product, but because of its expensive price, the domestic production is not large; organometallic complexes are also non-toxic, and the effect of plastisol is good, which is under development because of the same price problem. Because of the same price problem, currently under development.
2.4 Tackifier resin:
Role: is to improve the self-adhesive rubber and tire molding adhesion.
Composition: a variety of resins; traditional varieties of petroleum hydrocarbon resins, gumarone indene resin, rosin resins and terpene resins, etc., with the expansion of the use of synthetic rubber, all-steel radial tires and semi-all-steel radial tires and the development of the popularity of the pre-cured tires, the need for and has been out of the new varieties of viscosity-increasing resins.
Typical foreign products: Germany BASF company’s Koresin it is the condensation of tert-butyl phenol and acetylene. Koretack thermoplastic octyl phenol formaldehyde resin benzene series (i.e. SP 1068 resin).
Typical domestic products: according to the Sinopec Association of Science and Technology Office [2002] 005 notice: Shanghai Sans Agent Products Co., Ltd. in 2006 has been the successful development of p-tert-butylphenol formaldehyde resin, named KR-8 and commercialization, confirmed by many KR-8 is a Koresin resin of the same kind of products, the current KR-8 or super tackifier resin goods in the domestic sales and application of a large number of tire production, vulcanizing retreading tire production, vulcanization and curing. Tire production, vulcanization retreading and other past formulations with Koresin resin, reflecting good. Koresin resin has been included in the application of Koresin resin has been recognized by many aspects of the staff and attention.
Domestic widely used non-thermal reaction of phenolic resins and: 203 resin (i.e. SP1068), p-tert-octyl phenol formaldehyde resin. The manufacturers are:
204 resin – p-tert-butylphenol formaldehyde resin. Manufacturers are: Wuhan Jinghe Chemical Plant, Taiyuan Organic Chemical Plant and Changzhou Changjing Chemical Company (commodity TKB).
2.4.1 Viscosity increasing resin application status
As the radial tire production must use tackifying phenolic resin, imported Koresin resin is expensive, and the supply is insufficient, so a large part has been KR-8, 204 resin, 203 resin instead of; KR-8 price is only half of the imported products, the effect can be said to be the same, usually can be replaced by the same amount of 204 resin is known as “instead of Koresin”, you can add the same amount of 204 resin, the same amount of 204 resin. Koresin”, can be added to replace, to achieve the same effect, but can solve the resource and reduce costs.
At present, the most used resin is 203 resin, in addition to the domestic production plants, foreign capital SCS chemical (Shanghai) Co., Ltd. production of SP1058, Zhangjiagang Huaqi Chemical Co.
2.5 Binder:
Role: It refers to a kind of additives that can be added into the rubber mix to improve the bonding force of rubber and metal and various fiber products and other substances after vulcanization.
Composition: H.R.H (meso-alpha white) system, cobalt salt system and other systems.
2.5.1 Cobalt salt system
Including cobalt naphthenate, cobalt stearate, cobalt borate and cobalt aragonate, etc. It is mainly used for the adhesion of rubber and brass-plated or zinc-plated metal, and it is an important raw material for steel wire radial tires and other rubber-metal composite products.
Typical foreign products: Manoband 680C (cobalt boronylide 23) and Manoband 740C (cobalt neodecanoate) of Manchem Company in Britain.
At present, some domestic products of the company’s cobalt boronylide, has reached the foreign advanced level, Jiangyin City, Sanliang Chemical Co., Ltd. of SL-Co20.5 in the 740C based on the improvement of production technology and application has been no problem.
However, due to the scarcity of cobalt resources in China, still need to be imported, and the production of cobalt salt enterprises and small, and scattered, can not be imported to foreign cobalt resources, resulting in the high cost of raw materials, so that the competitiveness of the decline. At present, there are not many enterprises that have formed a climate, and the annual output still stays at several hundred tons, which is far from meeting the domestic demand.
At present, the imported products amount to 60%.
2.5.2 Methyl white system
2.5.3 Other systems:
2.6 Anti-coking agent
Role: Rubber will produce early vulcanization during storage and processing, so anti-coking agent refers to a kind of auxiliary that can improve the storage stability of vulcanized rubber and the safety of calendering under high temperature.
Anti-coking agent CTP is a more ideal species, also known as PVI, both have the same structure.
Composition: N-cyclohexyl thiophthalimide
2.7 Coupling agent
Function: It can effectively connect the inorganic group and organic polymer closely, so as to improve the processing performance and physical and mechanical properties of the rubber material.
Composition: there are many kinds of coupling agent, at present, the most widely used are silane coupling agent and titanate coupling agent.
Typical foreign products: Germany Degussa Si-69
Typical domestic commodity: Nanjing Shuguang Chemical Group Co., Ltd. The main grades are tetrasulfide KH–845–4 (Si-69) and disulfide SG–Si996 (Si-75). It has formed a production capacity of 6000 tons/year, and its production technology, production scale and product quality have reached the international advanced level.
2.8 Reinforcing resin, also known as reinforcing and hardening resin and resin for improving physical properties.
Role: used in the need for high hardness, high reinforcement and due to the increase of carbon black, sulfur yellow can not meet the requirements.
Composition: Phenolic resins are more widely used at present:
Typical foreign products: U.S. Occidental Durez12686,12687,12987 series, U.S. Polymer Application SP6600,6601,6700,6701 series and PA-52-056,070,083,108 series, Germany BASFKoreforte series, and France CECA,R series. BASFKoreforte series from Germany and CECA,R series from France.
Typical domestic products: 205 resin (H-promoting should be added to the formula) produced by Wuhan Jinghe Chemical Co., Ltd, Taiyuan BQ-205, PF-C reinforcing resin of Changjing Chemical Co. 206 resin (H-promoting has been added to the formula) produced by Wuhan Jinghe Chemical Co., Ltd, PF-H reinforcing resin, and H-containing reinforcing resin of Shanghai Kega Chemical Factory.
2.8.1 Resins for improving physical properties
With the development of rubber product performance and requirements, in recent years there are products such as Shanghai Sansi Auxiliary Products Co., Ltd RT-260 resin, this product can significantly improve the tire tread formula after aging elongation and tear resistance retention rate; it has been used for many years for tire strip flower and improve the flower and the base of the cleft. Improve the performance of flower and anti-chipping and chunking.
2.9 Spraying agent
Function: to improve the quality of tire lining and appearance.
Composition: according to its use in the outer tire on the different parts, usually there are internal and external points.
a. External spraying agent is divided into solvent type and water-based type. Because of the solvent-type external spraying agent is harmful to human body, it is now basically not used. The water-based external coating agent gives the tire a good ability to identify the color rubber, flame retardant, non-polluting, can increase the cleaning cycle of the mold and reduce the advantages of equipment investment, and therefore widely used.
b. Internal spraying agent is used to spray the inner surface of the molded and uncured tires, its main role is to make the outer tire is easy to release the mold, easy to pull out the curing capsule from the inner cavity of the outer tire and improve the quality of the tire and the appearance of the tire, to improve the rate of product qualification.
Foreign countries have used the third generation of products, but domestic attention is not enough, has not developed similar products.
Typical foreign commodities: U.S. Struktol permalease 10,80.polydis 121, Qingdao Angji mold Li 935p.
Typical domestic commodities: Changshu Delun Fine Chemical Factory tire with internal and external spraying agent series; Qingdao Dewei Fine Chemical Co., Ltd. mold release agent and chemical aerosol 12.
2.10 Mold release agent .
Role: make the mold release operation easy and prevent the damage to the product caused by forcible removal.
Composition: The mold release agent is generally divided into two types: external type and internal type, external type, i.e., coated on the surface of the mold cavity, customarily called isolation agent, the disadvantage of easy to leave mold scale and traces of corrosion on the mold, the price is expensive, etc., the internal release agent is generally in the form of auxiliary in the refining of the rubber when adding, it is very convenient to use, and the long-term maintenance of the mold is beneficial. In addition, the mold release agent also helps the flow of rubber, reduce the heat generated by the molecular friction, is a real multi-functional additives, therefore, in foreign countries called “internal lubricant”.
Typical foreign products: American Angstroms Moulderi 935P
Typical domestic commodities: Qingdao Dewei Fine Chemicals Co.
There is no mold release agent with excellent performance for various rubber products.
2.11 Anti-return agent
Role: mainly for thick products vulcanized rubber at high temperatures will be vulcanized back to the original, that is, crosslinking depolymerization problem.
Composition: m-xylene supported bis(citrofuryl) imide.
Typical foreign products: Flax Perkalink 900
Typical domestic products: Sanmenxia Xiawei Chemical Co., Ltd. anti-vulcanization reagent xiawei2000
2.12 Pre-dispersed masterbatch:
Function: save the amount of additives, shorten the mixing time, convenient for automatic transportation and metering, no dust and environmental pollution.
Composition: additives and active ingredients + polymer (EPDM and polyvinyl acetate EVA) Typical foreign commodities: Germany LANXESS Rhein Chemie Rhenogan, U.S.-funded Kunshan Yateman Chemical Co.
Typical domestic commodities: Jiangsu Lianlian Chemical Co., Ltd. produces a variety of rubber chemicals pre-dispersed masterbatch nearly 30 series, with a total production capacity of 10,000 tons, Dongguan Pulte Auxiliaries Ltd. also produces pre-dispersed masterbatch.
3. Foreign processing aids on behalf of the example
4. Domestic processing aids on behalf of the example
5. Problems
5.1 Original products with independent property rights are almost none.
5.2 Key products such as homogenizers, dispersants, etc. still need to be imported in large quantities.
5.3 Except for a few products such as anti-scorch CTP, coupling agent Si-69, etc., the quality of most of the products is still unsatisfactory compared with that of foreign countries.
5.4 A few toxic products, such as pentachlorothiophenol plasticizer, etc., are still widely used because of the cheap price, resulting in the promotion of new non-toxic products difficult.
Summary
With the rapid development of China’s rubber industry, especially in recent years the rise of radial tires, driven by the rubber processing aids industry, products from scratch, from small to large, a few of them, such as coking agent, silane coupling agent has accounted for the world’s first; but at present our country’s processing aids are still in the primary stage, in particular: originality with independent property rights of the product is almost non-existent, and some of the key products such as homogenizing agent, dispersant, etc. are still in need of a new product to promote non-toxicity. dispersant, dispersant and so on still need to import a large number of products. There is still a certain gap between the quality of many products and that of foreign countries.
