In this article, Polynorbornene (PNB)/Zinc dimethacrylate (ZDMA)/Dicumyl peroxide (DCP) composites can form dual‐crosslinking networks, which contain an ionic crosslinking network, and a part of the C─C covalent crosslinking network. DCP was used to initiate the polymerization of ZDMA to form ionic crosslinking bonds. With the increase of ZDMA, the total crosslink density (V_r) and ionic crosslink density (V_r2) increased. DCP was consumed in ZDMA polymerization, which made the PNB reduce the covalent crosslinking networks. Leading to the covalent crosslink density (V_r1) decreased. Compared with covalent crosslinking network, the dual‐crosslinking networks stored more energy when deformed, provided better restoring force and a higher shape recovery ratio for materials. When ZDMA exceeded 3.9 wt%, the ZDMA aggregates hindered the movement of molecular chains leading to the shape recovery ratio slightly decreased. When ZDMA was 2.4 wt%, the composite had an optimum shape fixing and shape recovery ratio. This article provided the experimental basis for the research of PNB dual‐crosslinking networks, also widened the research of PNB shape memory materials. © 2020 Wiley Periodicals Inc. J. Appl. Polym. Sci. 2020, 137, 48955.

中文翻译：

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双交联网络对聚降冰片烯形状记忆性能的影响

在本文中，聚降冰片烯（PNB）/二甲基丙烯酸锌（ZDMA）/过氧化二枯基（DCP）复合材料可以形成双交联网络，该网络包含一个离子交联网络和一部分C-C共价交联网络。DCP被用来引发ZDMA的聚合以形成离子交联键。随着ZDMA的增加，总交联密度（V _r）和离子交联密度（V _{r 2}）增加。DCP在ZDMA聚合中被消耗掉，这使PNB减少了共价交联网络。导致共价交联密度（V _{r 1}）减少。与共价交联网络相比，双交联网络在变形时可存储更多能量，从而为材料提供了更好的恢复力和更高的形状恢复率。当ZDMA超过3.9wt％时，ZDMA聚集体阻碍了分子链的运动，导致形状恢复率略微降低。当ZDMA为2.4重量％时，该复合材料具有最佳的形状固定和形状恢复率。本文为PNB双交联网络的研究提供了实验依据，也拓宽了PNB形状记忆材料的研究领域。©2020 Wiley Periodicals Inc. J.Appl。Polym。科学 2020，137，48955。