Compatibilization and properties of ethylene vinyl acetate copolymer (EVA) and thermoplastic polyurethane (TPU) blend based foam

• Published in: Polymer bulletin (Berlin, Germany) Vol. 71; no. 9; pp. 2219 - 2234
• Main Authors: Ma, Jianzhong, Shao, Liang, Xue, Chaohua, Deng, Fuquan, Duan, Zhouyang
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.09.2014; Springer; Springer Nature B.V
• Subjects: Applied sciences; Cellular; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Compatibility; Compatibilizers; Complex Fluids and Microfluidics; Compressive strength; Copolymers; Diphenyl methane; Elongation; Ethylene vinyl acetates; Exact sciences and technology; Forms of application and semi-finished materials; Fourier transforms; Interface reactions; Maleic anhydride; Mechanical properties; Organic Chemistry; Original Paper; Physical Chemistry; Physical properties; Plastic foam; Plastic foams; Polymer blends; Polymer industry, paints, wood; Polymer Sciences; Polyurethane foam; Scanning electron microscopy; Soft and Granular Matter; Spectrum analysis; Tear strength; Technology of polymers; Tensile strength; Urethane thermoplastic elastomers; Zinc oxides; China; Japan; Taiwan; Thermoplastic polyurethane; Foam; Compatibilizer; Ethylene vinyl acetate copolymer; Strengthening; Polymer blends; Graft copolymer; Property composition relationship; Mechanical properties; Thermoplastic rubber; Elongation strength; Compressive strength; Experimental study; Cellular plastic; Tensile strength; Thermal stability; Polyurethane elastomer; Thermal properties; EVA; Foaming process; Morphology; Preparation; Plastics; Tear strength
• ISSN: 0170-0839; 1436-2449
• DOI: 10.1007/s00289-014-1183-5

Ethylene vinyl acetate copolymer/thermoplastic polyurethane (EVA/TPU) blending foams are rarely reported so far because of their poor compatibility, and addition of a compatibilizer to the blend system was our major interest, which can improve interfacial adhesion between the two phases. In this paper, TPU-grafted EVA (EVA- g -TPU), as a compatibilizer, was simply prepared using maleic anhydride-grafted EVA (EVA- g -MAH) and 4,4′ diamino diphenyl methane in the mixing process of TPU and EVA matrix. Fourier transform infrared spectroscopy and differential scanning calorimetry were used to investigate the structures of EVA- g -TPU and the interfacial reaction in the mixing process, and the effect of EVA- g -TPU on compatibilization between the two phases of EVA/TPU blends was investigated using scanning electron microscopy. Finally, EVA/EVA- g -TPU/TPU foams based on the good compatibility of the resin blends were prepared, and the physical properties directly related to the compatibility were investigated as a function of the theoretical quantity (molar mass) of EVA- g -TPU ( n EVA- g -TPU ) in the foams. Moreover, the tensile strength, elongation at break, tear strength and compression set were improved by 19.0, 9.3, 43.6 and 7.5 %, respectively. Overall, EVA/EVA- g -TPU/TPU foams with excellent mechanical properties were obtained without sacrificing other important physical properties (lower density etc.) through popular and friendly means in this research.