Study On Synthesis And Modification Of Polydicyclopentadiene

Polydicyclopentadiene (PDCPD) is a crosslinked plastic of three-dimensional network with a high flexural modulus and impact strength. It has attracted worldwide attention also due to its excellent mechanical properties, weather resistance, wear resistance, surface coating, electrical insulation, water resistance and so on. Furthermore, the raw material, dicyclopentadiene (DCPD) is rich in resources with low price. In recent years, the studies on modified polydicyclopentadiene also starts to become a new hotspot.In this study, the first generation Grubbs catalyst has been synthesized. Its structure is characterized by1H-NMR,13C-NMR and31P-NMR. PDCPD is synthesized by this catalyst. The results of FI-IR test shows that DCPD is polymerized in ring-opening metathesis polymerization. There are a large number of trans-unring C=C double bonds, and some parts of cyclopentene polymerize in ring-opening metathesis polymerization. It results in a certain degree of crosslinking.In the previous work, the best polymerization conditions of PDCPD was determined at nDCPD:ncat=1000:l, temperature of45℃and reaction time of10min with the curing conditions of2hours for80℃,120℃and150℃. It has good thermal stability with Td5%=163.2℃, Td10%=247.7℃, Td max=441.8℃, char yield of14.6%and Tg of78.6℃. PDCPD also has a good acid and alkali resistance. Its weightlessness is lower than1.2%in acidic and alkaline solution during30days.Here, PDCPD is modified by N,N’-4,4’-diphenylmethane-bismaleimide (BDM) and Norbornylene (NB) to synthesize BDM/polyDCPD and NB/polyDCPD. Their thermal stability is better than PDCPD and Tg is raised to94.7℃and89.9℃. Impact resistance of BDM/polyDCPD is low, while that of NB/polyDCPD is better than PDCPD. Therefore, both BDM/polyDCPD and NB/polyDCPD have excellent chemical resistance. Their weightlessness is lower than1%in acidic and alkaline solution during30days.