PHBV/TPU/cellulose compounds for compostable injection molded parts with improved thermal and mechanical performance

Poly(hydroxybutyrate-co-valerate) (PHBV) is a biopolymer that has gained a lot of attention because of its biodegradability, good thermal resistance, and balanced mechanical properties with respect to some commodity plastics. However, it presents two big limitations that hinder its potential application in replacing plastics for rigid injected parts: high cost and low toughness. Aiming at overcoming these limitations, the use of two additives in a PHBV matrix was explored: thermoplastic polyurethane (TPU) as an impact modifier and cellulose as reinforcing filler. Compounds of PHBV with different TPUs and cellulose contents were prepared by extrusion and, subsequently, injection molding. The morphology, thermal, and mechanical properties of the so-obtained materials were analyzed. Also, the biodisintegrability under standard composting conditions of the studied compositions was also assessed. The results of this work show that the obtained PHBV/TPU/cellulose compounds are biodisintegrable and show balanced properties in terms of thermal resistance–stiffness–toughness. These properties point these compounds as potential candidates to replace commodities in rigid part applications that require biodisintegration in their end-of-life, being able to be processed in a conventional injection molding industrial facility

Composite foams made from biodegradable polymers for food packaging applications

Polymeric foams are cell structures (porous microstructures) that have been frequently made from synthetic polymers for use in the development of food packaging. Due to the problems concerning the environmental impact caused by polymers from the petrochemical industry, the foams have been more recently studied from biodegradable polymers. However, the polymer materials obtained are usually susceptible to moisture, thus conditioning the collapse of the porous structure of the material. As an alternative, the composite foams have been investigated from nanofillers such as clays, cellulose, nanoparticles, among others. This chapter aims to analyze the recent advances in the studies of composite foams.Fil: Araque Moreno, Luis Miguel. Federal University Of Piauí; BrasilFil: Alvarez, Vera Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Gutiérrez Carmona, Tomy José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin

On the use of nanocellulose as reinforcement in polymer matrix composites

AbstractNanocellulose is often being regarded as the next generation renewable reinforcement for the production of high performance biocomposites. This feature article reviews the various nanocellulose reinforced polymer composites reported in literature and discusses the potential of nanocellulose as reinforcement for the production of renewable high performance polymer nanocomposites. The theoretical and experimentally determined tensile properties of nanocellulose are also reviewed. In addition to this, the reinforcing ability of BC and NFC is juxtaposed. In order to analyse the various cellulose-reinforced polymer nanocomposites reported in literature, Cox–Krenchel and rule-of-mixture models have been used to elucidate the potential of nanocellulose in composite applications. There may be potential for improvement since the tensile modulus and strength of most cellulose nanocomposites reported in literature scale linearly with the tensile modulus and strength of the cellulose nanopaper structures. Better dispersion of individual cellulose nanofibres in the polymer matrix may improve composite properties

การวิเคราะห์การผสมพลาสติกชีวภาพพอลิแลคติกแอซิดและเทอร์โมพลาสติกสตาร์ช

วารสารวิชาการและวิจัย มทร.พระนคร, ปีที่ 14, ฉบับที่ 2 (ก.ค.-ธ.ค. 2563), หน้า 98-109This research was concentrated on characterized mechanical properties and adjusted compatibility of poly (lactic acid) (PLA) with thermoplastic starch (TPS) as biodegradable polymers composites. PLA was blended with TPS at the proportion of 10, 20, 30, 50, and 70 wt% as well as 2 phr chain extender by an internal mixer at 200°C. The blended materials were then injection molded at 230°C. Tensile testing showed that as the amount of TPS increase, the elongation at break tended to increase but the tensile strength and modulus tended to decrease. The morphology was investigated by scanning electron microscope. It was found that distinct phase between PLA and TPS was observed. Yet, adding the chain extender clearly improved the compatibility between PLA and TPS. The blended materials were also analyzed by differential scanning calorimetry method to study thermal properties. It was found that, as the amount of TPS increased, the glass transition temperature (Tg), melting temperature (Tm), and cold crystallization temperature (Tcc) deceased. Additionally, chain extenders did not affect thermal properties. The thermal stability of the composites decreased when increasing the amount of TPS because of the degradation of TPS in PLA. However, when heated at 100ºC for 1 hr, the PLA sample bent while TPS did not bend. When PLA was mixed with TPS, the composite was bent according to adding TPS.Rajamangala University of Technology Phra Nakho