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The production of linear low-density polyethylene (LLDPE) yarns for artificial turf is an advanced extrusion process, which relies heavily on the polymer's semicrystalline structure and inherent strengthening mechanisms to obtain the tailored mechanical properties so typical for turf yarns: a combination of strength and resilience. This review aims to bring together all relevant aspects in the structure–materials–processing interaction triangle which is so strongly in evidence in this application, by first summarizing the specific structural origins of the properties of the semicrystalline LLDPE and then discussing how structure evolves during the different steps of the production process, to eventually come to the final product properties of the yarn. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44080.

Three-dimensional plotting, a melt-based technique that involves the guided deposition of extruded filaments, is a promising method for the manufacture of thermoplastic scaffolds for tissue engineering. However, the polymer degrades during processing because of a prolonged residence time at an elevated temperature in the dispensing head before actual extrusion. This thermal degradation has been attributed to random chain scission; in this research, it has been quantified as a function of the residence time for a selection of polylactide-based polymers. The utilized techniques include thermogravimetric analysis (overall mass loss), differential scanning calorimetry (glass-transition, melting, and recrystallization temperatures), gel permeation chromatography (molecular mass), and inherent viscosity measurements. Experiments have shown that a static heating interval greater than 6 h is sufficient to destroy the molecular chain integrity of poly-(1-lactide) and poly(d,l-lactide). Copolymers with poly(e-caprolactone) and poly(glycolic acid) are more resilient to thermal loading but are still severely affected. Overall, the differential scanning calorimetry results have been judged to be a good source of complementary data for the quantification of the degradation phenomenon, whereas inherent viscosity measurements have been confirmed to be related to the gel permeation chromatography results, which indicate shortening of the polymer chain.

This review provides state of the art information on the heat resistance of biobased thermoplastic materials. It gives an overview of the parameters used to indicate heat resistance, strategies to improve the heat resistance of (biobased) plastic materials and some current “heat resistant” commercially available biobased plastics materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42305.

A promising method for the manufacture of complex 3D ceramic parts is selective laser sintering (SLS). SLS of alumina components can be done either directly or indirectly. In this article, the indirect method is used by using polystyrene coated alumina particles. One of the methods to produce these alumina powders is dispersion polymerization. In this research, it is described how the alumina powder has been developed and tested. The powder has been characterized to define its processability within the SLS process. Used techniques include SEM (morphology), STA/TGA (overall mass loss), DSC (glass transition temperature Tg), and laser diffraction (particle size distribution). The investigated SLS process parameters were the preheating temperature, laser power, scan spacing, and scan speed. STA/TGA has proven that polystyrene‐coated alumina powders are suitable for SLS process, while DSC results were judged to be a good source of complementary data on preheating temperature of alumina/polystyrene powders. SLS experiments showed that single layer green parts can be produced. By using the optimized SLS parameters, it was demonstrated that different 3D geometries can be produced with the polystyrene coated alumina powders. ispartof: Journal of Applied Polymer Science vol:128 issue:3 pages:2121-2128 status: published