Study On Synthesis And Properties Of Anti-pollution Antioxidants

Rubber products play an important role in our daily lives,which can seen in all walks of life,such as tires,rubber soles,sealing rings,convey or belts and so on.However,during long-term storage and usage of rubber products,there will be changes in appearance and degradation in property.This phenomenon is called"Rubber Ageing".The main reason is that under the influence of external factors such as oxygen,heat,light,zone and so on,the weak internal structure of the rubber chains are destroyed,which causes the ageing reaction.The ageing of rubber is an inevitable process,but it can delay this process by adding antioxidants.Antioxidant is auxiliary agent that must be added during the processing of rubber products.Its presence can effectively reduce the ageing speed of rubber,thereby prolonging the life of rubber products and indirectly improving the efficiency of the enterprise.Antioxidant 4020(6PPD,DMPPD)is a widely usedantioxidants in rubber products.It has the advantages of excellent protection performance,low price,mature processing technology and so on.But it also has some disadvantages—toxic,color pollution,low migration resistance and so on.Especially the low migration resistance,as a result,it is very easy to migrate out of the rubber,which not only cause pollution to rubber products and surrounding environment,but also reduces its own protection efficiency.Some studies have pointed out that the larger molecular weight of the antioxidant,the more stable and better the migration resistance.Therefore,the purpose of my research is to react the antioxidant 4020 with other compounds to increase its molecular weight,thereby improving its migration resistance.This article mainly includes the following three parts:(1)Introduction part.This part introduced the ageing of rubber,rubber antioxidant and some related content of synthesis,and discussed in depth the relevant knowledge of rubber ageing and protection from various aspects.(2)Synthesis part.In this part,Ciba Irgazone 997 was synthesized and another two innovative new antioxidants were independently designed.The design ideas are based on the antioxidant 4020.The long-chain compound containing epoxy groups undergoes ring-opening addition reaction with 4020,which has benn modified novel antioxidant with high molecular weight after being characterized by FTIR HNMR?LCMS and so on.The results showed that three antioxidants were successfully synthesized.According to the different reactants,we named three antioxidants as 997,SH12 and EP14.(3)Proterties test.The topic added different antioxidants to natural rubber and then conducted a series of perpormance evaluations,including protection of thermal oxygen and ozone,oxidation induction period,migration resistance and so on,to compare properties with antioxidant 4020.About the testing methods of migration,on the basic of previous studies,the topic expanded several testing methods both apparent comparison and quantitative anlysis by using HPLC.The results showed that the protection properties of 997,SH12 and EP14 are similar to antioxidant 4020 and the migration resistance is significantly improved compared to antioxidant 4020,which is basically consistent with the expected results.