Chain Extension, Phase Interface Reparation and Mechanical Property of Recycled Acrylonitrile‐Butadiene‐Styrene by Epoxidized Styrene‐Butadiene‐Styrene

Abstract

For ABS, the styrene-acrylonitrile (SAN) block copolymer phase is the matrix phase, polybutadiene (PB) phase is the disperse phase, and styrene-acrylonitrile block copolymer grafted polybutadiene (SAN-g-PB) is the compatibilizer. [9] From the viewpoint of processing, ABS from the discarded products can be processed repeatedly for reuse. [10] However, as a result of aging arising from the service, the mechanical properties of recycled ABS (R-ABS) are usually inferior to virgin ABS (V-ABS), especially the decreased impact strength. This limits the application and reuse of R-ABS. [10] Recycling is an efficient way to manage and treat waste plastics. It has been a significant section of industry since plastics now involve every aspect of our living. [11-25] The International Organization for Standardization (ISO) and the American Society for Testing and Materials (ASTM) have standardized the classification and there are four main techniques for recycling waste plastics. These include reuse (primary), mechanical recycling (secondary), chemical recycling (tertiary), and energy recovery (quaternary). [26-28] Plastic recycling is a valuable practice to save 20-50% from the point of market price in comparison with their virgin counterparts. [29,30] However, lots of recycled The demand for processing recycled acrylonitrile-butadiene-styrene copolymer plastics (R-ABS) grows fast. Herein, epoxidized styrene-butadienestyrene (ESBS) with reactive groups including polybutadiene (PB) phase, epoxidized polybutadiene (EPB) phase and polystyrene phase is prepared by modifying SBS with an in situ peroxyformic acid method. Both chain extension and phase interface reparation of R-ABS are successfully reported by simple melt blending. Compared with R-ABS, when ESBS content is 15 wt%, the average molecular weight (M w) of the ESBS/R-ABS is increased from 118.01 to 612.51 kDa. The particle size of the dispersed phase is decreased obviously. The compatibility between these two phases became better. The average notch impact strength of R-ABS is 5.72 kJ m −2. When the ESBS content is 15 wt%, the average notch impact strength of ESBS/R-ABS reaches 13.90 kJ m −2 , which is increased by 143% compared with that of R-ABS. The notch impact strength of ESBS/R-ABS is close to that of virgin ABS. The reported high-value usage of R-ABS has a great potential for industrial-scale applications.