双环戊二烯反应注塑

作为一种新型工程材料,近年来聚双环戊二烯(polydicyclopentadiene, PDCPD)的研究备受关注。PDCPD多采用反应注塑成型工艺,需要在反应前有足够的储存稳定期以保证物料的混合和注模。本文介绍了不同催化体系的优缺点,着重阐述了极具应用前景的新兴Grubbs潜伏型催化剂最新进展,包括热触发型、化学触发型和光触发型等,并对其结构、性能及反应机理进行了详细分析。同时,围绕配体结构对催化特性的影响,对如何提高催化剂的潜伏性且保持其催化活性进行了对比和剖析。其中,螯合结构和O、S、N等杂原子基团的引入,提高了催化剂的潜伏性,但催化活性会有一定程度的下降。此外,还评述了聚双环戊二烯改性方面的相关研究,并对聚双环戊二烯产业发展的趋势进行了展望。

Reaction Injection Molding of Dicyclopentadiene

As a new thermosetting polymer with excellent mechanical properties,polydicyclopentadiene(PDCPD) which often produced by reaction injection molding(RIM) has received many interests.Before polymerization,enough pot life should be necessary for mixing and injecting processes.The advantages and disadvantages of different catalytic systems used in RIM are described in the paper.Furthermore,the development of latent Grubbs catalyst is dominantly reviewed.Latent catalysts which attack more attention in the industry exhibit no activity in the presence of monomer or substrate under room temperature,but can be triggered quantitatively to a highly activation by thermal,chemical or photochemical activation to initiate the metathesis reaction.The catalyst structure and proprieties as well as the mechanism are also discussed.The introduction of chelating structure and heteroatom such as O,N,S,both reduce the initiation rate of catalyst,lead to the improvement of latent performance.However,this also has negative impact on the activity of catalyst.Besides that,we focus on the impact of ligand’ structure on the properties,so as to gain ideal latent catalyst with good performance of latenty,but not with the cost of catalyst’s activities.The research in the copolymer of dicyclopentadiene is also described.At last,the future research in the area is prospected.