Influence of thermal and morphological characteristics on mechanical responses of polypropylene/γ-irradiated elastomer blends

Preparation and Properties of Poly(ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate)/Polyglycolic Acid (PETG/PGA) Blends

Polyglycolic acid (PGA) is used as a reinforcing component to enhance the mechanical properties of poly(ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) (PETG). The tensile performance, micromorphology, crystallinity, heat resistance, and melt mass flow rates (MFRs) of PETG/PGA blends with varying PGA contents were studied. Both the tensile yield strength and tensile modulus of the PETG/PGA blends increased gradually with an increase in the PGA content from 0 to 35 wt%. The tensile yield strength of the PETG/PGA (65/35) blend increased by 8.7% (44.38 to 48.24 MPa), and the tensile modulus increased by 40.2% (1076 to 1509 MPa). However, its tensile ductility decreased drastically, owing to the poor interfacial compatibility of PETG/PGA and the oversized PGA domains. A multiple epoxy chain extender (ADR) was introduced into the PETG/PGA (65/35) blend to improve its interfacial compatibility and rheological properties. The tensile performance, micromorphology, rheological properties, crystallinity, and heat resistance of PETG/PGA (65/35) blends with varying ADR contents were studied. The strong chain extension effect of ADR along with its reactive compatibilization improved the rheological properties and tensile ductility. By carefully controlling the ADR concentration, the performance of PETG/PGA blends can be regulated for different applications.

New, Effective, and Low-Cost Dual-Functional Binder for Porous Silicon Anodes in Lithium-Ion Batteries

In this work, a new effective and low-cost binder applied in porous silicon anode is designed through blending of low-cost poly(acrylic acid) (PAA) and poly(ethylene- co-vinyl acetate) (EVA) latex (PAA/EVA) to avoid pulverization of electrodes and loss of electronic contact because of huge volume changes during repeated charge/discharge cycles. PAA with a large number of carboxyl groups offers strong binding strength among porous silicon particles. EVA with high elastic property enhances the ductility of the PAA/EVA binder. The high-ductility PAA/EVA binder tolerates the huge silicon volume variations and keeps the electrode integrity during the charge/discharge cycle process. EVA colloids acting as host materials for electrolytes increase the electrolyte uptake of electrodes. The porous silicon electrode with the PAA/EVA binder exhibits a reversible capacity of 2120 mA h g^-1 at 500 mA g^-1 after 140 cycles because of the excellent ductility and lithium-ion transport properties of the PAA/EVA binder.