Liu Chaozheng, Mei Changtong, Xu Bing, Chen Weimin, Yong Cheng, Wang Ke, Wu Qinglin
College of Materials and Engineering, Nanjing Forestry University, No.159 Longpan Road, Nanjing 210037, People's Republic of China.
School of Renewable Natural Resources, Louisiana State University, Baton Rouge, LA 70803, USA.
R Soc Open Sci. 2018 May 9;5(5):180074. doi: 10.1098/rsos.180074. eCollection 2018 May.
Weathering of wood--plastic composites (WPCs) leads to discoloration and cracks, which greatly limits their outdoor application. In this study, light stabilizers (including UV-327, HS-944 and nano-SiO) were added to the shell of a co-extruded high-density polyethylene-based WPC to improve its anti-ultraviolet (UV) ageing properties and simultaneously to maintain its good mechanical properties. The results showed that UV-327 was the most effective light stabilizer for improving the mechanical and anti-UV ageing properties of the composites among the three stabilizers used. WPC samples combined with 2% UV-327 had the highest retention rates in flexural strength and also had the smoothest surface after 2500 h of UV ageing. The samples with 2% UV-327 added had the best protection for discoloration, showing the lowest values of Δ* (colour difference) and Δ* (luminescence) in all samples after 2500 h of UV ageing. WPC samples with 2% UV-327 were also oxidized the least after 2500 h of UV ageing. The results reported herein serve to enhance our understanding of the efficiency of light stabilizers in preventing UV degradation of WPCs, with a view to developing co-extruded WPCs with low cost, high anti-UV ageing properties and good mechanical properties for outdoor applications.
木塑复合材料（WPC）的老化会导致变色和开裂，这极大地限制了它们在户外的应用。在本研究中，将光稳定剂（包括UV-327、HS-944和纳米SiO）添加到共挤出的高密度聚乙烯基WPC的外壳中，以改善其抗紫外线（UV）老化性能，同时保持其良好的机械性能。结果表明，在所使用的三种稳定剂中，UV-327是改善复合材料机械性能和抗UV老化性能最有效的光稳定剂。添加2%UV-327的WPC样品在弯曲强度方面具有最高的保留率，并且在UV老化2500小时后表面也最光滑。添加2%UV-327的样品对变色具有最佳的防护效果，在UV老化2500小时后的所有样品中显示出最低的Δ*（色差）和Δ*（发光度）值。在UV老化2500小时后，添加2%UV-327的WPC样品的氧化程度也最低。本文报道的结果有助于增强我们对光稳定剂在防止WPCs紫外线降解方面效率的理解，以期开发出具有低成本、高抗UV老化性能和良好机械性能的用于户外应用的共挤出WPCs。
