Acrylonitrile–butadiene rubber functionalization for the toughening modification of recycled poly(ethylene terephthalate)

Abstract

The incorporation of functionalized acrylonitrile–butadiene rubber (NBR) into recycled poly(ethylene terephthalate) (PET) was introduced as an effective route for modifying the properties of PET and as a new method for PET recycling as well. To achieve modified NBR, glycidyl methacrylate (GMA) was grafted onto NBR with optimized reactive mixing, in which the highest grafting degree and lowest gel content were generated. PET/NBR blends with and without GMA functionalization were produced by melt mixing, and the mechanical properties, dynamic mechanical thermal properties, and phase morphologies of the systems were determined and compared. We found that low amounts of peroxide initiator (dicumyl peroxide) and high levels of the GMA monomer in the presence of the styrene comonomer led to the maximum grafting degree and suppressed the competing rubber crosslinking and GMA homopolymerization reactions. The blend compatibility with PET determined from dynamic mechanical thermal analysis spectra and scanning electron microscopy images was greatly improved when the NBR‐grafted GMA was used instead of the neat NBR in the blend recipes. As a result, the rubber phase dispersed in the PET matrix more finely, and the impact strength of the blend advanced very significantly. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40483.

A study on the fracture, mechanical and thermal properties of chain extended recycled poly(ethylene terephthalate)

“…1,20,21 In the literature, it appears that especially GMA-based impact modifiers are widely used for polyesters (such as PET) because of the reaction tendency between glycidyl functionality and terminal groups of polyesters. 22,23 Xanthos et al 22 used diimidodiepoxide as a novel chain extender for PET and compared reactivity of diimidodiepoxide with that of GMA copolymer. Their results indicated that the reactivity of diimidodiepoxide chain extender is higher than GMA copolymer even at lower loading level.…”