Trends in the Development of Rubber Additive Technology in Our Country

The rubber additive industry in our country has already established a certain research and development foundation. In the future, it is necessary to conduct collaborative research based on market demand among enterprises, research institutes, and universities to promote technological progress in the industry.

1 Accelerate the industrialization and product diversification of processing operation system additives.

The processing operation system additives in our country started relatively late and there are not many varieties, so development efforts need to be increased. Although the usage of processing operation system additives is small, there are many varieties and they are quite complex, with a high technical content. They play an important role in improving processing technology, enhancing production efficiency, and product quality in the rubber processing industry.

The dispersing agent is used to improve the mixing uniformity of rubber with different polarities and viscosities. Companies like S&S in Germany and Rhein Chemie have a series of products available in the market, but domestic production has not yet been scaled up. The 40MSF series of dark aromatic hydrocarbon resin mixtures from S&S is suitable for NR, SBR, BR, EPDM, NBR, etc. It can improve the mixing uniformity of rubber with different polarities and promote the rapid dispersion of fillers. Its 60NSF series of light-colored aliphatic hydrocarbon resin mixtures is suitable for light-colored rubber materials. It is evident that to meet the strong specificity requirements, it is necessary to produce a series of products.

Tackifying resins are especially suitable for multi-layer rubber composite products. Although we have industrialized some varieties in recent years, there are still gaps. For example, BASF's Koresin super tackifying resin series, which is a tert-butyl phenol acetylene resin, can keep the surface tackiness of rubber for several weeks, but it still needs to be imported. In terms of bonding agents for tire cord rubber, American Cytec has many products, and the recently launched single-component, low-cost, environmentally friendly bonding resin Cyrez CRA132 series is an advanced and novel self-condensing product. Even in the absence of a methylene acceptor, its internal melamine-based self-condensing components can form cross-linking, and the bonding quality is superior to HMMM and zinc salt products. The development ideas for this new product are worth our reference.

Processing operation system additives also include dispersants, plasticizers, release agents, and anti-scorch agents, all of which are specialized additives that form their own systems. Dow Corning's silane release agents and internal coatings have excellent performance and are favored by domestic users. The silane coupling agent St-75 developed by Nanjing Shuguang Chemical Factory has a low content of tetrasulfide and some disulfide, which reduces scorch tendency. Changzhou Shuguang Chemical Factory has successfully developed a pre-dispersed methacrylate bonding system with good dispersion effects. The RM series of composite metal salts developed by Zhenjiang Jinwei Group Co., Ltd. is priced low, which helps users reduce costs. These products should accelerate the pace of industrialization.

2 Continue technological transformation of anti-aging agents and accelerators to develop new varieties.

Accelerators and anti-aging agents are the most widely used additives, so the advancement of their production technology has always been a research hotspot both domestically and internationally. Nanjing Chemical Factory will carry out technological transformation on aniline-based anti-aging agents, using hydrogenation reduction technology to produce RT Peisi, reducing pollution and improving quality, thus laying a good raw material foundation for producing high-quality 4020 and 4010NA. Amine, thiourea, and sulfonamide accelerators are all synthesized using oxidative condensation processes. Traditional processes require the use of oxidants such as sodium hypochlorite and sodium nitrite, resulting in significant waste. Domestic research has developed oxygen catalytic oxidation processes, hydrogen peroxide oxidation processes, and electrochemical synthesis processes, significantly reducing waste and aligning with the development trend of "clean processes." The oil filling and granulation technology for accelerator powders has been adopted in Tianjin, Shandong, and other places, and further technological transformation needs to be accelerated. Different types of accelerator blends are also sold abroad, and varieties with synergistic effects can be blended together to form new products with unique properties. This is also the direction for future research and development of new products.

Since Germany controlled the content of N-nitrosamines in the air in 1988, manufacturers in various countries have taken measures to switch to safe accelerators. In recent years, NOBS and other accelerators containing amine groups have been undetectable in European and American radial tires. Amino-based accelerators NS and CZ have become the dominant varieties. The production and sales volume of NS in our country is increasing year by year, and the production of CZ can fully meet market demand. In the future, NS should continue to be promoted to expand its usage. Additionally, new safe accelerators are still under development, with TBSI showing superior performance compared to NS, and research has been conducted by Nanjing Chemical Factory and others. There should also be research on safe accelerators made from dicyclopentadiene as raw materials, as well as other varieties without nitrosamine toxicity issues.

The characteristics of future additives should be non-toxic, environmentally friendly, and reasonably priced. For example, the Duravzon 37 series of anti-aging agents from Uniroyal, which contain triazine rings, have no color pollution and are ideal anti-aging agents for dynamic and static rubber products against oxidation and ozone, with advantages such as slow migration speed, resistance to extraction, and low volatility.