Structural changes and mechanical performance of recycled poly(vinyl chloride) bottles exposed to ultraviolet light at 313 nm

Abstract

ABSTRACT:The structural changes and mechanical performance of virgin poly(vinyl chloride) (PVC) bottle (VB) compounds blended with postconsumer PVC bottles collected from a specified factory (RB-F) and houses (RB-H), were examined before and after UV irradiation at 313-nm UV wavelength for different periods of time up to 28 days. The results indicated that, when exposed to UV light, the RB-F/VB blends containing greater conjugated double bonds with higher yellowness index appeared to exhibit better mechanical performance than that of the RB-H/VB blends. It was found that the amount of conjugated double bonds was not a linear function of the discoloration level of PVC compounds. Tensile strength of the VB compounds was not affected when incorporated with RB-F recyclate, but progressively decreased with increasing RB-H recyclate. An optimum concentration for RB recyclates to be added into the virgin compound was recommended for obtaining a maximum impact strength. Both tensile and impact strengths decreased with increasing UV exposure time, a severe degradation being obvious after a UV exposure time of 21 days. Hardness was not affected significantly by the addition of PVC recyclate, but increased with increasing UV exposure time.

Wood plastic composites weathering: Visual appearance and chemical changes

“…In addition, degradation of PP-based WPC increased with an increase in wood content [12,13]. For HDPE-based WPC (50% wood content) color fade continued throughout 2000 h of weathering [14]. Results of Lundin [15] showed the depth of 50% wood-flour-filled HDPE lightening was 0.3 mm after 2000 h of weathering.…”

Degradation mechanism and mechanical properties of PVC in PVC‐PE melt blends: Effects of molecular architecture, content, and MFI of PE

“…Sombatsompop et al [5,6] studied the recycling possibilities of various PVC products (pipes and bottles, and cables) in terms of processabilities, mechanical and thermal properties, and morphological properties. Overall experimental results indicated that the addition of recycled PVC strongly affected the rheological, mechanical, and thermal properties of PVC products, the optimum content to be added being dependent on the recycled types (which were associated with the initial chemical compositions of PVC compound), the loading level of recycled PVC, and UV light [7].…”

Weathering of Compounded Products

“…476 The recycling of plastic bottles is still a major problem because of degradation and contamination with other polymers. 480 Pulverization slightly reduces the problem.…”