Abstract: This study investigated the feasibility of using fibers obtained by the recycling of end life cathode ray tubes glasses (EOL-CRT glass) as new filler for polypropylene material. The effects of these new fibers on the mech. properties of plastic composites were studied. Fracture surfaces were investigated by SEM. Based on the findings of this work, it appears evident that these new fibers can be used instead of com. glass fibers providing good mech. and thermal properties. Moreover the matrix modification in the hybrid composite led to better mech. performances.
Abstract: In view of the environmental problem involved in the management of WEEE, and then in the recycling of post-consumer plastic of WEEE there is a pressing need for rapid measurement technologies for simple identification of the various commercial plastic materials and of the several contaminants, to improve the recycling of such wastes.
This research is focused on the characterization and recycling of two types of plastics, namely plastic from personal computer (grey plastic) and plastic from television (black plastic). Various analytical techniques were used to monitor the compositions of WEEE. Initially, the chemical structure of each plastic material was identified by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). Polymeric contaminants of these plastics, in particular brominated flame retardants (BFRs) were detected in grey plastics only using different techniques. These techniques are useful for a rapid, correct and economics identification of a large volumes of WEEE plastics.
Abstract: Nanocomposites of polycarbonate (PC) reinforced with nanosized silica particles were prepd. by a melt mixing technique in an internal mixer. Two kinds of com. hydrophilic fumed silicas differing in their sp. surface area were added in amts. up to 5% by vol., and their reinforcing action was compared to that of organically modified silica, loaded in the same amts. Particle-matrix interactions were investigated by means of rheol. and dynamic-mech. thermal anal., demonstrating the important role played by the org. modification in the interactions with the polymer matrix, and showing an optimal nanoparticle loading around 2 vol%. The scratch resistance of the nanocomposites obtained from hydrophilic silicas was investigated, and a remarkable enhancement in the indenter's penetration resistance was obsd. for all the compns. with respect to pristine PC. The same behavior was obsd. for the Shore D hardness and for the impact resistance of the nanocomposites that also significantly improved with the max. load shifting from a min. value of 521 N for pristine PC up to values grater than 1330 N for the nanocomposites, demonstrating the activation of effective mechanisms of energy dissipation due to the presence of the nanofillers.
Abstract: Several techniques of polymer characterization and different aging methods have been used with the aim of developing a simple, fast and reliable method to qualify com. pipe-grade polyethylene samples, and possibly to evidence the presence of recycled PE within PE pipes. The results of the different techniques used have been compared with respect to their capability to evidence differences in the degrdn. rate of different HDPE samples (including virgin HDPE, HDPE pipes obtained from virgin HDPE and HDPE pipes that probably contain recycled HDPE). FT-IR, TGA and DSC were found unsuitable for this purpose but, on the contrary, MFI measurements have been found sensitive enough to evidence different degrdn. rates when a suitable combination of high temp., oxygen, mech. stresses and mixing time had been used for aging the sample.
