A new strategy using non-isothermal crystallization and supercritical CO2 processing is found to promote the electroactive phase content in PVDF.

Biobased polylactic acid (PLA) foam packaging has been commercialized as an alternative to conventional polystyrene (PS) foam. However, PLA’s low glass transition temperature results in its inherently poor heat resistance and in turn limits the application to cold-fill packaging. In this study, low-density PLA foam sheet was extruded using an industry-scale tandem extrusion line and subsequently laminated with a PLA film casted from a high heat deflection temperature (HDT) PLA resin with a very low d-lactide monomer content (i.e., ∼0.4 mol %). Experimental results reveal that the crystallization behaviors of PLA foam sheets were sensitive to both thermoforming temperature and process-induced strain. Furthermore, this work has demonstrated that heat-resistant biodegradable PLA foam sheets could be realized by laminating them with solid films made of high-HDT PLA to serve as environmentally sustainable alternatives to PS foams in hot-fill packaging applications.

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Background: Present study investigates the effect of adding nanoclay particles and foaming conditions on cellular properties of ABS/Nanoclay nanocomposite foams. Methods: For this purpose, first nanocomposite components are mixed using a twin-screw extruder. The amount of added nanoclay is considered 2 and 4 percentage by weight. Also, poly methyl methacrylate (PMMA) with the percentages of 2 and 4 wt% are used as the compatibilizer. Distribution of nanoclay particles in ABS matrix is examined using X-ray diffraction test. Then, nanocomposite samples are produced using injection molding process and foamed using batch foaming process. CO 2 gas is used as the physical blowing agent of the foaming process. The saturation time of samples and the effect of adding of nanoclay on CO 2 sorption/desorption rate was assessed by gravimetric method prior to foaming experiments. Then, nanocomposite samples are foamed under different process conditions according to a Taguchi L9 orthogonal array. Results: The obtained results reveal that adding nanoclay increases the cell density and decreases both foam density and cell size of ABS/nanoclay composite foams compared to the pure ABS foams. Conclusions: Results show that the structural properties of nanocomposite foams depend on both processing parameters and percentage of nanoclay in the nanocomposite specimens.