Effects of Antioxidants on Photodegradation of Wood Flour/Polypropylene Composites during Artificial Weathering

Yao Peng, Ru Liu, Jinzhen Cao

Abstract


The influence of antioxidants and of their compound systems were evaluated relative to the photodegradation of wood flour/polypropylene (WF/PP) composites using ultraviolet accelerated weathering. Six groups of samples were exposed in an accelerated weathering tester for a total duration of 960 h. The surface color, gloss, and flexural properties of the samples during weathering were tested. In addition, the weathered surfaces were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TG). The results revealed the following: (1) after weathering, all samples showed significant color fading and gloss change; (2) composites containing antioxidants showed less loss of flexural strength, fewer surface cracks, and better thermal stability after weathering than the control composite; (3) the crystallinity of polypropylene increased in weathered samples due to recrystallization of lower molecular weight polypropylene; and (4) antioxidant 168 (AO-168) was beneficial to color stability at the early stage of weathering, while composites containing 0.2% antioxidant 1010 (AO-1010) and 1.0% AO-168 (AO-1) maintained the highest retention ratios of flexural properties during weathering.

Keywords


Wood flour/polypropylene composites; Antioxidants; Thermal properties; Photodegradation

Full Text: PDF

Welcome to BioResources! This online, peer-reviewed journal is devoted to the science and engineering of biomaterials and chemicals from lignocellulosic sources for new end uses and new capabilities. The editors of BioResources would be very happy to assist you during the process of submitting or reviewing articles. Please note that logging in is required in order to submit or review articles. Martin A. Hubbe, (919) 513-3022, hubbe@ncsu.edu; Lucian A. Lucia, (919) 515-7707, lucian.lucia@gmail.com URLs: bioresourcesjournal.com; http://ncsu.edu/bioresources ISSN: 1930-2126