MINGYU HE¹, AMATJAN SAWUT¹, LI GUAN², YING LI¹, MAMATJAN YIMIT²

Journal of Polymer Materials, Vol.38, No.3-4, pp. 191-203, 2021, DOI:10.32381/JPM.2021.38.3-4.2

Abstract The weathering performance of polypropylene (PP) was studied in an artificial accelerated weathering chamber of 340 nm ultraviolet light and natural conditions in Turpan, China. This work aimed to provide a method for calculating the aging failure of PP under natural conditions by the means of artificial accelerated aging. SEM showed that large crack widths of approximately 1.25 µm and 1.63 µm appealed on the PP surface after 15 days artificial accelerated aging and 150 days natural aging, respectively. XPS data revealed that the number of C-O and C=O bonds on the PP surface were generally the same after artificial… More >

Ruyuan Yang¹, Haitao Li^2,*, Assima Dauletbek^1,2, Mahmud Ashraf^2,4, Rodolfo Lorenzo³, Youfu Sun¹, Yuehong Wu¹

Journal of Renewable Materials, Vol.9, No.7, pp. 1293-1307, 2021, DOI:10.32604/jrm.2021.015296

Abstract This paper presents an experimental investigation to identify suitable indices to assess durability of glulam when subjected to freeze-thaw cycles in an exposed enviroenment. In this study, two types of glulam specimens were tested for their performance when subjected to different levels of aging due to freezing and thawing. Effect of aging treatment on various parameters including thickness swelling rate, static bending strength, elastic modulus, shear strength, and peeling rate of adhesive layer were studied. Obtained results showed that freeze-thaw aging treatment did not affect the water-resistance of the specimens as measured by thickness swelling rate and had little effect… More >