Preparation And Modification Of Polydicyclopentadiene

Polydicyclopentadiene (polyDCPD) is a kind of high-performance thermoset resin with good processing properties and mechanical properties, receiving extensive attention in recent years. With the development of the research and application, it puts forward more and more requirements on the material properties, which make the research on improving the mechanical and thermal properties of polyDCPD needed further development. Rencently, adding other components into DCPD to modify polyDCPD has become a new research hotspot.Firstly, the method for preparing polyDCPD with the first generation Grubbs’catalyst through ring-opening metathesis polymerization (ROMP) has its disadvantages. Differential scanning calorimetry (DSC) is utilized to study the kinetics of the polymerization of DCPD and determine the curing process. Meanwhile, the effects of the amount of catalyst on polyDCPD mechanical properties, corrosion resistance, swelling properties are studied. The results show that the flexural strength and flexural modulus of polyDCPD show a decreasing trend after increasing firstly with the reduce of catalyst. When nDCPD:nCat=1000:1, the flexural strength and flexural modulus of polyDCPD reaches the maximum,42.1MPa and1258.8MPa, respectively.Secondly, we prepare the composites (tyxy-CNT/polyDCPD and mGO/polyDCPD) by filling different morphologies of nano-particles (α-CNT and mGO) into the polyDCPD, the mechanical and thermal properties of the composites are studied. The results show that a-CNT could toughen polyDCPD, the elongation at break increased by259.6%when adding1.0wt%a-CNT; mGO could both enhance and toughen polyDCPD, the tensile strength increased by33.1%, the tensile modulus increased by116.7%and elongation at break increased by230.9%when adding1.0wt%mGO. Otherwise, both the G’ and Tg of mGO/polyDCPD increased. Thermal stability of a-CNT/polyDCPD and mGO/polyDCPDare significantly improved.Finally, phenolphthalein-containing bismaleimide (PPBMI) is added into DCPD, and PPBMI reinforced polydicyclopentadiene (poly(PPBMI/DCPD)) are prepared, and the mechanical and thermal properties are studied. The results show that the flexural strength of poly(PPBMI/DCPD) increase first and then decrease with increasing PPBMI content, while the flexural modulus gradually increase. Thermal stability of poly(PPBMI/DCPD) is significantly increased comparing to the unfilled polyDCPD, both the G’and To of poly(PPBMI/DCPD) increased. Otherwise, the rigid monomer DMB and flexible monomer DCPE are prepared. Then, adding them into DCPD respectively to prepare poly(DMB/DCPD) and poly(DCPE/DCPD), and the thermal and mechanical properties are studied. The results show that thermal performance of poly(DMB/DCPD) have been enhanced with an increasing amount of DMB. Whereas, the thermal stabilities of the poly(DCPE/DCPD) have been weakened with an increasing amount of DCPE. The impact strength increase first and then decrease with increasing DMB content, and G’ of Poly(DMB/DCPD)increase significantly compared with unfilled polyDCPD. The bending-rebound relaxation time of poly(DCPE/DCPD) displays a minimum value at60wt%loading of DCPE.