Study On Synthesis Of PDCPD And Copolymer

Polydicyclopentadiene is a novel high performance thermoset engineering plastics, it has high flexural and impact strength, and is a both rigidity and toughness of engineering plastics. Moreover, Polydicyclopentadiene has some adventages,like lightweight, chemically resistant, low water absorption, good painting.These take a broad application of polydicyclopentadiene.In this study,The first generation Grubbs catalyst has been synthesized, and it’s structure was characterized by1H-NMR,13C-NMR and31P-NMR. Then PDCPD has been synthesized by this catalyst. The results of FI-IR test shows DCPD has been polymerized in ring-opening metathesis polymerization. There are a large number of trans-unring C=C double bond, and only part of cyclopentene polymerize in ring-opening metathesis polymerization, this takes a certain degree of crosslinking and lead PDCPD to be uncrytalline.During investigated conditions of polymerize, the best polymerization conditions is determined which is nDCPD:ncat=800:1, polymerization temperature of45℃, reaction time10min, after curing conditions is curing2h at80℃, curing2h at120℃and curing2h at150℃. Between these factors ratio of monomer and catalyst has the greatest impact in conversion rate of monomer and polymer property. Polymer mechanics tests show that PDCPD is tough and strong material, increasing the amount of catalyst can improve the tensile strength and tensile modulus of PDCPD, but bending strength and impact strength will decline. PDCPD has a good acid and alkali resistance,its weightlessness is lower than1.2%in acidic and alkaline solution during30days, with the increasing of catalyst the weightlessness will decrease. PDCPD shows a good thermal stability after cured, it’s Td5%=375.7℃, Td10%=400.7℃and Td max=423.8℃, the residual carbon is28.85%.Cyclopentadiene-styrene copolymer (PDCPD-St) is synthesized by the first generation Grubbs catalyst, the kineticanalysis shows the optimum reaction conditions is nDCPD:ncat1000:1,5%(wt%) content of styrene, reaction time90min. The results of FI-IR and1H-NMR test shows PDCPD-St has been polymerized in ring-opening metathesis polymerization. There are a large number of trans-unring C=C double bond and part of cyclopentene, which is symmetry. Thermodynamic studies shows that glass transition temperature(Tg) of DCPD-co-St reduced with styrene content increasing, and PDCPD-St shows a good thermal stability,Td10%=318.8℃,Td max=452.3℃,the residual carbon was28.9%,as uncured PDCPD.