The Thermally Reversible Covalent Crosslinking Of Acrylate Containing Active Chlorine

It is well known that cyclopentadiene(CPD) can be converted todicyclopentadiene (DCPD) at room temperature and DCPD can beconverted to CPD at high temperature, which is the famous Diels-Alderreaction. Potassium salt of dicyclopentadiene acid(DCPD(COOK)2), aderivative of cyclopertadiene was used as a crosslinking agent for thevulcanization of acrylic rubber(ACM) through esterification between thecrosslinking agent and active chlorine of ACM. Because the crosslinkedstructure is thermally reversible, the "vulcanized "ACM can become anew type thermoplastic elastomer(TPE). In order to obtain the thermally reversible crosslinked ACM, thefollow studies were focus on the extrude reaction and thermo-modelreaction. Firstly, the crosslinking reaction of ACM filled of white carbon blackwith DCPC(COOK)2 was conducted by thermo-model methods. Theeffects of dosage of crosslinking agent, model temperature, the kinds anddosage of catalysts on the mechanical properties were studied in detail.All the results showed that the crosslinked ACM's mechanical propertieshave a good lever and can be reformed for three times. It also be provedthat the crosslinked ACM can be reformed is due to DCPD converted toCPD by contrast to the crosslinking reaction of potassium salt of adipatewith ACM. Secondly, in the extrude reaction of DCPC(COOK)2 with ACM, thegel content of crsslinked ACM can reach to more than 90% and morethan 60% of them were thmally reversible. The effects of dosage ofDCPC(COOK)2, catalysts and its dosage, the temperature and the rotatespeed of screw on the crosslinked ACM were also investigated in detail.The chart of IR can prove that DCPC(COOK)2 do react with the activechlorine of ACM. It also can be proved that the structure of DCPD canbe destroyed at over 180℃.