The toughening of polymeric glasses using cellulose without sacrificing transparency

摘要

The development of cellulose graft copolymers has been intensively studied during recent years. Our previous works have demonstrated that cellulose graft strategy can greatly improve the mechanical properties of thermoplastic elastomers. However, the effect of cellulose graft strategy on glassy polymers is still unknown. Herein, Cellulose-graft-poly(methyl methacrylate) (Cell-g-PMMA) copolymers were synthesized by activators regenerate by electron transfer atom transfer radical polymerization (ARGET ATRP). Two kinds of celluloses, microcrystalline cellulose (MCC) and wood pulp cellulose (Pulp) were used as starting materials. Thermal behavior, transparency, and mechanical properties of these graft copolymers were investigated. Compared with the brittle fracture of PMMA, a typical ductile fracture was observed in both MCC-g-PMMA and Pulp-g-PMMA copolymers, which showed similar transparency as linear PMMA film. The tensile toughness of MCC-g-PMMA copolymers was almost 7 times to that of linear PMMA. Furthermore, the toughness of Pulp-g-PMMA copolymers was even better than that of MCC-g-PMMA copolymers.