Polystyrene-Free Chain Extenders for Recycled Poly(ethylene terephthalate)

Chain extenders are additives introduced to economically and efficiently restore the performance of recycled condensation polymers such as poly(ethylene terephthalate). The most widely used commercial chain extenders for recycled poly(ethylene terephthalate) (rPET) is the Joncryl ADR (ADR) family of copolymers which are composed of styrene, glycidyl methacrylate (GMA), and butyl acrylate (BA). However, polystyrene is prone to degradation at higher temperatures. Thus, the aim of this study was to create polystyrene-free chain extenders for rPET recycling. Polystyrene-free chain extenders were synthesized via free radical polymerization from GMA, BA, and acetylated hydroxyethyl methacrylate (HEMA-Ac) or benzoylated hydroxyethyl methacrylate (HEMA-Bz) to enhance the thermal and mechanical properties of rPET. These chain extenders were analyzed by 1H NMR spectroscopy, size exclusion chromatography, and differential scanning calorimetry. The chain extender (1 phr) was then blended with rPET by melt reactive extrusion, resulting in mechanical and thermal properties comparable to those of the commercial chain extender ADR. These additives offer safe alternatives to ADR and will enable the recycling of large volumes of rPET and other condensation polymers without generating any harmful residual styrene

Clear Antismudge Unimolecular Coatings of Diblock Copolymers on Glass Plates

Two poly­[3-(triisopropyloxysilyl)­propyl methacrylate]-<i>block</i>-poly­[2-(perfluorooctyl)­ethyl methacrylate] (PIPSMA-<i>b</i>-PFOEMA) samples and one poly­(perfluoropropylene oxide)-<i>block</i>-poly-[3-(triisopropyloxysilyl)­propyl methacrylate] (PFPO-<i>b</i>-PIPSMA) sample were synthesized, characterized, and used to coat glass plates. These coatings were formed by evaporating a dilute polymer solution containing HCl, which catalyzed PIPSMA’s sol–gel chemistry. Polymer usage was minimized by targeting at diblock copolymer unimolecular (brush) layers that consisted of a sol–gelled grafted PIPSMA layer and an oil- and water-repellant fluorinated surface layer. Investigated is the effect of varying the catalyst amount, polymer amount, as well as block copolymer type and composition on the structure, morphology, and oil- and water-repellency of the coatings. Under optimized conditions, the prepared coatings were optically clear and resistant to writing by a permanent marker. The marker’s trace was the faintest on PFPO-<i>b</i>-PIPSMA coatings. In addition, the PFPO-<i>b</i>-PIPSMA coatings were far more wear-resistant than the PIPSMA-<i>b</i>-PFOEMA coatings

Development of a Preliminary Framework for the Reduction of Plastics in Packaging

Plastic packaging causes much waste, and its sustainability is receiving increasing attention. Companies have made efforts to mitigate the environmental impacts of packaging; however, plastic waste from packaging remains a big issue. This study builds a framework of factors that are important in helping companies reduce the amount of plastic in their packaging. The framework is based on findings from a literature review and five interviews with practitioners. The study found that to achieve a reduction of plastic in packaging, seven factors are imperative in the fuzzy-end stage of packaging design and development