Energy‐efficient manufacturing of polymers with tunable mechanical properties by frontal ring‐opening metathesis polymerization

Abstract

Frontal polymerization (FP) is a process in which the heat generated by the self‐reaction transforms monomers to cured polymers. Here, in order to improve the flexibility of polydicyclopentadiene, comonomers (norbornene‐terminated polyether, ND‐230,400,2000) are designed and synthesized, which can copolymerize with dicyclopentadiene (DCPD) by FP. The polymers (ND) prepared by ND‐2000 and DCPD have tunable mechanical properties, from thermosets to elastomers. Specifically, the breaking elongation of the polymers can be varied 69‐fold, from 6.1% to 423.4% by controlling the proportion of ND‐2000. Among them, ND polymer with 50 wt% ND‐2000 has good elastic behavior without yield. And, the reaction mixture solutions of DCPD and ND‐2000 have the characteristics of controllable gel time and shear thinning, which make it have the potential of application in additive manufacturing.

Facile Utilization of Renewable Resources Containing Cyclobutene Mechanophores: Preparation and Properties of High-Toughness Materials with One-Step Cross-Linking by Frontal Ring-Opening Metathesis Polymerization

“…When subjected to tension, the possibility of intermolecular fracture increases, which also ultimately leads to a reduction in strength. However, it is worth noting that the material has excellent elongation at break compared to other studies, − which can be attributed to the fact that polycaryophyllene contains a large number of mechanophores.…”

“…Unlike COD, caryophyllene has only one double bond on its nine-membered ring, which prevents it from being polymerized into cross-linked materials by itself. The high toughness of caryophyllene and DCPD copolymers is attributed to the contribution of the cyclobutane ring structure in caryophyllene, compared with other copolymerization systems of DCPD. − In addition, when the proportion of caryophyllene is high (75%), the system still maintains the rapid prototyping characteristics of DCPD. The frontal polymerization method with low energy consumption and high efficiency can be used to produce products, which is suitable for three-dimensional (3D) printing and manufacturing parts. − This work can attach importance to the structural advantages of terpene natural products, providing a new method for the efficient use of renewable resources.…”

Free-Standing 3D Printing of Epoxy-Vinyl Ether Structures Using Radical-Induced Cationic Frontal Polymerization

“…Additive manufacturing (AM or 3D printing) using FP has been explored and reported in the literature. Frontal ring-opening metathesis polymerization has been used extensively to demonstrate the potential of 3D printing through FP. − The use of FP for 3D printing has advantages in energy consumption and the speed of printing. An ideal process will see that the front is initiated and propagates behind the extruded material very closely so that the resin does not sag, owing to suitable viscosity, and the front is continuous.…”