DOI: 10.1002/pen.70601 ISSN: 0032-3888
Structural and Mechanical Properties of Polymer Blends of Poly(
l
‐Lactic Acid)/Ethylene‐Vinyl Acetate Copolymer Containing Carboxymethylated or
TEMPO
Rokibul Hasan Rumon, Chisato Nara, Yuya Matsuo, Manato Yoshino, Atsuhiro Fujimori ABSTRACT
The effects of incorporating two types of cellulose nanofibers (CNFs) on the structural and physical properties of partially miscible crystalline/amorphous polymer blends as the matrix were investigated. Approximately 1 wt% of carboxymethylated CNFs (CMCNFs) or TEMPO‐oxidized CNFs (TOCNFs) was introduced into a 3:1 polymer blend composed of poly(
l
‐lactic acid) (PLLA) and ethylene‐vinyl acetate copolymer (EVA). The resulting composites were evaluated in terms of thermal behavior, crystallinity, and mechanical properties. The addition of both CMCNFs and TOCNFs slightly reduced the onset crystallization temperature of the PLLA:EVA polymer blend with a weight ratio of 3:1. In contrast, both CNFs enhanced the overall crystallinity and crystallite size of the polymer blends. In addition, the incorporation of CMCNFs or TOCNFs led to substantial improvements in Young's modulus and maximum stress. The spherulite size of the polymer blends containing CNFs tended to decrease, indicating the influence of heterogeneous nucleation due to the addition of nanofibers as nucleating agents.