Background and overview[4]
Anti-aging agent MB (chemical name is 2-mercaptobenzimidazole). This product is mainly used to manufacture transparent rubber products, white or light-colored products, and foam latex products. Zhang Zuoxin and others studied the effect of the amount of antioxidant MB on the aging resistance of EPDM rubber. The research showed that in the antioxidant 2246/MB system, the amount of antioxidant MB had basically no effect on the vulcanization characteristics of the blend rubber; when the antioxidant When the MB dosage is 1.5 parts, the performance and retention rate of the blended rubber after aging are better, and the tensile strength and elongation at break during the aging process are both higher.
Preparation[1]
Rubber antioxidant MB is synthesized from the direct esterification reaction of acrylic acid and 2,2′-ethylene bis(4,6-di-tert-butyl)phenol. The mechanism is to first generate acrylic acid chloride, and then react with bis Phenol H esterification reaction. HCl is continuously generated during the reaction, and the alkaline acid-binding agent triethylamine can react with HCl in time to form triethylamine hydrochloride, which is dispersed in the reaction solution as a solid. The existence of free triethylamine is a necessary condition for the reaction medium to remain alkaline. Changes in pH directly affect the speed of the esterification reaction and the change in the reaction equilibrium direction. In traditional processes, it is difficult to control pH to achieve the highest reaction rate.
CN201210460019.5 aims at the above technical problems and provides a preparation method of rubber antioxidant MB that can improve reaction efficiency, including the following steps:
(1) Add 2,2′-ethylenebis(4,6-di-tert-butyl)phenol, acrylic acid, and toluene into the reaction kettle in sequence, replace the air with nitrogen in the reaction kettle, heat, stir, and raise the temperature to 80-85 degrees Celsius, maintain temperature;
(2) Feed phosphorus oxychloride and complete it within 40-50 minutes. At the same time, add the acid binding agent triethylamine, adjust the feeding speed, control the pH of the reaction solution, and measure the pH every 5 minutes to keep the pH at 8.0 Narrow range change; the feeding time of the acid binding agent is 120-130min, the feeding is completed, the temperature is maintained at 80-85 degrees Celsius, and the insulation reaction is 90-95min;
(3) After the reaction is completed, cool the reaction solution to room temperature, discharge the material, and obtain the reaction mixture as a solid-liquid mixture; wash with toluene and dry.
The present invention provides an online method for adjusting the synthesis of an acid-binding agent. The pH of the reaction solution is adjusted to a weakly alkaline narrow range. Under the conditions of determining suitable synthesis reaction parameters, the product has high yield, good quality, and low production costs. Low, easy for industrial production.
Application[2-3] [6]
CN201210502905. Anti-aging agent D, spray carbon black, o-dibutyl ester softener; the specific component content in weight percentage is: styrene-butadiene rubber-10: 30~50 parts; butadiene rubber: 70~100 parts; accelerator TT: 1 ~2 parts; sulfur: 0.3~0.6 parts; zinc oxide: 4~6 parts; stearic acid: 1~3 parts; antioxidant D: 2~4 parts; spray carbon black: 20~40 parts; o-dibutyl ester Softener: 10 to 12 parts; anti-aging agent MB 1 to 3 parts.
By changing the ratio of rubber components, the resistance of rubber seals for instruments to heat, cold, water and acid can be improved, and the leakage of sealing medium caused by aging, hardening and discoloration of rubber seals for instruments can be avoided, and sealing can be delayed. service life of parts.
CN201210503098.3 provides a heat-resistant rubber tube, which is at least butyl rubber and is characterized by: it also includes sulfur, accelerator M, accelerator TT, zinc oxide, magnesium oxide, stearic acid, paraffin, Anti-heat aging agent D, aluminum silicate and calcium carbonate, the specific component content in weight percentage is: butyl rubber: 80~120 parts; sulfur 1~2 parts; accelerator M0.3~0.5 parts; accelerator TT0 .8~1.2 parts; zinc oxide 3~5 parts; magnesium oxide 3~5 parts; stearic acid 0.8~1.2 parts; paraffin 2~4 parts; thermal aging agent D1~1.3 parts; aluminum silicate 50~80 parts ; 40 to 60 parts of calcium carbonate; 1 to 3 parts of antioxidant MB.
By adding anti-heat aging additives in a certain proportion to the formula, the performance of the rubber in absorbing hot oxygen free atoms at high temperatures is improved, and the reaction caused by contact between hot oxygen free atoms and the rubber main chain is avoided, making the rubber heat-resistant. The rubber tube has significantly improved heat resistance compared with existing rubber tubes.
CN201610778576.X provides an engine mounting compound and a preparation method thereof. The engine mounting compound includes the following parts by weight of raw materials:�Laminated glue: 100 parts, zinc oxide: 3 to 5 parts, stearic acid: 1.5 to 3 parts, antioxidant 77PD: 1.0 to 1.5 parts, antioxidant S?TMQ: 0.8 to 2 parts, antioxidant MB: 1.0~ 2.0 parts, paraffin: 2.0~5.0 parts, carbon black: 20~60 parts, modified silica R300: 5~10 parts, naphthenic oil T3367: 3~10 parts, dispersant 42M: 0.5~1 part, silane Coupling agent: 1.5 to 3 parts, sulfur: 2.0 to 2.5 parts, accelerator CBS: 0.8 to 1.5 parts, accelerator DM: 0.2 to 0.5 parts, anti-sulfide reducing agent PK900: 0.5 to 1.5 parts.
The engine mounting rubber of the present invention has the efficient protective effect of the antioxidant 77PD and the antioxidant S-TMQ, the protective synergistic effect of the antioxidant MB, and the softening and plasticizing properties of the high-viscosity, high-flash-point naphthenic oil T3367. , and the combination of ordinary vulcanization system and anti-vulcanization reducing agent PK900 can improve the dynamic fatigue durability and heat resistance of the rubber compound, so that the engine mounting colloid made of it has better high-temperature durability.
Main reference materials
[1] CN201210460019.5 Preparation method of rubber antioxidant MB
[2] CN201210502905.X Aging-resistant rubber seals for instruments
[3] CN201210503098.3 A heat-resistant rubber tube
[4] Zhang Zuoxin, Yu Xiang, Deng Tao. Effect of antioxidant MB dosage on the aging resistance of EPDM rubber blends [J]. Rubber and Plastic Technology and Equipment, 2019, 45(01):26 -29.
[6]CN201610778576.X engine mounting compound and preparation method thereof