The properties of recycled PVC bottle compounds. 1: Mechanical performance

Abstract

The properties of recycled W C bottle material separated from the post-consumer waste stream were investigated. In the first part of this study, attention was focused on the mechanical properties. In order to examine the effects of recycling, the properties of the recycled material were compared with those of virgin W C and pure material that had been processed into bottles and then granulated. The effects of pulverization of the recycled material were also studied. The mechanical properties investigated included tensile, fatigue, and environmental stress cracking tests, in conjunction with fracture surface examination. molecular weight determination, and i m p~~-Q analysis. It was found that the recycled material did show significant reduction in strength and ductility, though pulverization improved the situation considerably. The main reason for this was the presence of impurities. especially PET, which although present at levels below 0.5%. had a large effect on the properties. IlpTIlODUCTIONver the past ten years, there has been a growing 0 awareness that a more sustainable solution is required to deal with the large amount of plastic waste produced, especially from packaging applications. It is currently estimated that over ten million tonnes of plastic waste are generated in Western Europe each year (1). A breakdown of this into plastic type is shown in Fig. I, from which it is clear that the major contributors are the packaging materials of PE, W C . PP, and PS. As legislation and the cost of landfill drive the need to reduce the amount of plastic waste going to landfill sites, a greater emphasis will have to be placed on recycling as one of the options. Currently, less than 200h of plastics produced across Europe are recycled (2). with the purer in-house generated waste (such as off-cuts) accounting for a significant part of this. In order to increase the proportion of packaging materials that can be recycled, there are many economic and social issues to address, but also some important materials considerations, and it is these that form the basis of this study.As drink bottles provide one of the easiest routes to collection and separation, these have been targeted as a sensible area in which to concentrate recycling effort. The materials investigated in this study originated from the Reprise pilot-scale bottle separating plant operated by EVC Compounds Ltd. This study focuses on the WC collected from this plant, and attempts to deal with the issues that are important if such recycled material is to be treated with confidence as an alternative to virgin polymer. These issues in-iii) a better understanding of the properties of the recycled material, characterization of molecular weight changes, the levels of separation purity required in order to achieve acceptable properties, and the influence of the recycled material on subsequent reprocessing.Studies of the effects of recycling on the mechanical properties of polymers have generally concentxated on the short-term strength properties (3)(4)(5)(6)(7)(8). ...

Mechanical properties of recycled PVC blends with styrenic polymers

“…1), which corresponds to the carbonyl group at 1735 cm −1 , can be observed. Carbonyl groups are present in the stabilizers used in PVC 21. However, because of the nature of the credit card, it can be presumed that the presence of vinyl acetate is the main cause of the appearance of the carbonyl group, since this is added to increase flexibility.…”

Weathering of Compounded Products

“…Product-package interaction was studied to develop specific methods of testing. 477 Successful recycling of PVC collected from factory and households confirmed by analysis of results of bottles weathering after exposure to UV at 313 nm. 477 The mechanical properties of the new bottles are degraded when recycled material is added due mostly to the differences in particle sizes of regular and recycled materials.…”

“…474 Bottles with different solvents were stored at a reference temperature of 16 o C and in an accelerated test at a temperature of 50 o C. Depending on the type of liquid (mostly solvents) storage time varied between 6 months and five years. 477 The mechanical properties of the new bottles are degraded when recycled material is added due mostly to the differences in particle sizes of regular and recycled materials. 476 The recycling of plastic bottles is still a major problem because of degradation and contamination with other polymers.…”

Investigation of fatigue and mechanical properties of the pipe grade poly(vinyl chloride) using recycled scraps

“…Previous researches on the use of recycled PVC mainly focused on the blending of virgin and recycled PVC [5][6][7][8][9][10], the blending of recycled PVC with different polymers [11][12][13][14], and the effect of aging due to the repeated use of PVC [15]. However, most researches focused on the variation of static mechanical properties, and investigations on long-term durability are very scarce.…”

“…Ma and La Mantia [8] studied the variation of thermal stability and mechanical properties when using post-consumer PVC beverage bottles and recycled pipe-grade PVC. Arnold and coworkers [9,10] compared the mechanical properties of virgin and post-consumer recycled PVC. Ajji [13] investigated the variation of mechanical properties of virgin and recycled PVC and polyethylene (PE) based on additives and peroxides.…”