Analysis Of Structure And Properties Of Ethylene-propylene Rubber

EPDM with high ENB content produced by Jilin Petrochemical Company is J-5105.Its main purpose is to manufacture EPDM products with extrusion-continuous vulcanization.The EPDM with high ENB has the characteristics of fast vulcanization speed,but the J-5105 of Jilin Chemical Company has the problems of low vulcanization speed and high odor of rubber.We suspect that there are free ENB residues,so we need to establish a method to determine the content of free third monomer.For the J-5105 grade EPDM product supplied by PetroChina Jilin Petrochemical,in order to determine the content of the free third monomer in the sample,we use an indirect method.It was first extracted by Soxhlet extraction for 48 hours to ensure removal of the free small molecule ethylidene norbornene(ENB)in the rubber.Then,the content of double bonds in the rubber after the extraction was determined by iodine value method,Fourier infrared method and 'H-NMR method,and the percentage of free ENB in the total ENB of the original rubber was determined to be 13.11%,13.62%and 14.91%,respectively.It was found that the results determined by the iodine value method were reproducible and the results were more accurate.Ethylene propylene diene monomer(EPDM)with high ethylene content produced by Jilin Chemical Company is difficult to mix uniformly with carbon black and other reinforcing fillers due to its storage in winter.Therefore,we need to study the effect of cryogenic storage on the mixing process,the structure and properties of blends and vulcanizates,and compare it with the performance improvement of nitrogen-filled 3080 and 3092PM.We firststore the high ethylene content of 3080P,nitrogen-filled 3080 and foreign grade 3092PM EPDM at-23? for 0 days,7 days,14 days,21 days,using XRD and DSCto describe the crystallization of rubber compound.It is then processed using the formulation of the sealing strip and its processing properties,mixing performance and vulcanization performance are determined.It was found that EPDM after low temperature storage,the performance of 3092PM was better than that of 3080 grade rubber,and it was found that filling the 3080 grade rubber with nitrogen can improve its performance after low temperature storage.