Manufacturing and properties of biobased thermoplastic composites from poly(lactid acid) and hazelnut shell wastes

This is the peer reviewed version of the following article: Balart, J.F., Garcia-Sanoguera, David, Balart, Rafael, Boronat, Teodomiro, Sanchez-Nacher, Lourdes. (2018). Manufacturing and properties of biobased thermoplastic composites from poly(lactid acid) and hazelnut shell wastes.Polymer Composites, 39, 3, 848-857. DOI: 10.1002/pc.24007 , which has been published in final form at [Link to final article using the DOI]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Poly(lactic acid), PLA-based green composites were obtained with hazelnut shell flour (HSF) derived from the food industry thus leading to fully biodegradable materials with attracting properties. The hazelnut shell flour content varied in the 10-40wt% range. An increase in the degree of crystallinity with increasing HSF was detected, mainly due to the nucleating effect of lignocellulosic particles. The thermodimensional stability was noticeably improved with increasing HSF amount as evidenced by a remarkable decrease in the coefficient of thermal-linear expansion. Increasing HSF leads to stiffer materials as HSF particles act as interlock points that restrict polymer chain motion. Addition of hazelnut shell flour as filler in PLA-based green composites leads to fully biodegradable composites with balanced mechanical and thermal properties. Furthermore, it gives a solution to upgrade wastes from the hazelnut industry and contributes to lower the cost of PLA-based materials. POLYM. COMPOS., 39:848-857, 2018. (c) 2016 Society of Plastics EngineersContract grant sponsor: Ministerio de Economia y Competitividad-MINECO; contract grant number: MAT2014-59242-C2-1-R; contract grant sponsor: Conselleria d'Educacio, Cultura i Esport; contract grant number: GV/2014/008.Balart, J.; Garcia-Sanoguera, D.; Balart, R.; Boronat, T.; Sanchez-Nacher, L. (2018). Manufacturing and properties of biobased thermoplastic composites from poly(lactid acid) and hazelnut shell wastes. Polymer Composites. 39(3):848-857. doi:10.1002/pc.24007S84885739

Utilization of Renewable Biomass and Waste Materials for Production of Environmentally-Friendly, Bio-based Composites

The introduction of renewable biomass into a polymer matrix is an option competing with other possibilities, such as energy recovery and/or re-use in the carbonized state, or production of chemicals, such as, in the case of ligno-cellulosic waste, concentrates on the production of simple sugars, then possibly leading to the development of biopolymers. These competitive applications have also some interest and market, however with a considerable energy, water and materials consumption, due also to the not always high yielding. Other possibilities for renewable biomass are therefore being used as fillers to increase mechanical performance of polymers or to allow e.g., the absorption of toxic chemicals. This review concentrates on the use of biomass as close as possible to the “as received” state, therefore avoiding whenever suitable any thermal treatment. More specifically, it focuses on its introduction into the three categories of oil-based (or bio-based replacement) of engineered polymers, into industrial biopolymers, such as poly(lactic acid) (PLA) and self-developed biopolymers, such as thermoplastic starch (TPS)

Isothermal Melt Crystallization Kinetics of PP/organoclay Blends

Polystyrene (PP)/organoclay (OMMT) blends were prepared by co-rotating twin-screw extruder. The effects of OMMT on isothermal crystallization behaviors of blends was studied by differential scanning calorimetry (DSC). Using Avrami equation analysis the crystallization kinetics of materials. The analysis result shows that the OMMT act as effective nucleating agents, accelerating the crystallization of PP, then lead the rate of crystallization increased. Avrami exponent n is between 2.04~3.57, which indicating that PP/OMMT blends crystallization process might correspond to a two-dimensional or three-dimensional growth process. The activation enerigies for isotheraml crystallization were determined by the Arrhenius equation