PBS-Based Green Copolymer as an Efficient Compatibilizer in Thermoplastic Inedible Wheat Flour/Poly(butylene succinate) Blends

Abstract

Considering the current context of research aiming at proposing new bioplastics with low costs and properties similar to fossil-based commodities currently on the market, in the present work, a hybrid blend containing a prevalent amount of cheap inedible cereal flour (70 wt %) and poly(butylene succinate) (PBS) (30 wt %) has been prepared by a simple, eco-friendly, and low-cost processing methodology. In order to improve the interfacial tension and enhance the adhesion between the different phases at the solid state, with consequent improvement in microstructure uniformity and in material mechanical and adhesive performance, the PBS fraction in the blend was replaced with variable amounts (0–25 wt %) of PBS-based green copolymer, which exerted the function of a compatibilizer. The copolymer is characterized by an ad hoc chemical structure, containing six-carbon aliphatic rings, also present in the flour starch structure. The two synthetic polyesters obtained through two-stage melt polycondensation have been deeply characterized from the molecular, thermal, and mechanical points of view. Copolymerization deeply impacts the polymer final properties, the crystallizing ability, and stiffness of the PBS homopolymer being reduced. Also, the prepared ternary blends were deeply investigated in terms of microstructure, thermal, and mechanical properties. Lastly, both pure blend components and ternary blends were subjected to disintegration experiments under composting conditions. The results obtained proved how effective was the compatibilizer action of the copolymer, as evidenced by the investigation conducted on morphology and mechanical properties. Specifically, the mixtures with 15 and 20 wt % Co appeared to be characterized by the best mechanical performance, showing a progressive increase of deformation while preserving good values of elastic modulus and stress. The disintegration rate in compost was found to be higher for the lower amount of copolymer in the ternary blend. However, after 90 days of incubation, the blend richest in copolymer content lost 62% of weight.

Artificial Ageing, Chemical Resistance, and Biodegradation of Biocomposites from Poly(Butylene Succinate) and Wheat Bran

“…In addition, the bran grains swelling due to water absorption facilitate the penetration of microorganisms accelerating the degradation of WB. Thus, after the biological decomposition of the filler, the surface of active interaction of water and microorganisms on PBS macromolecules increases [4,[142][143][144]. The significant increase in biodegradation kinetics of PBS in compost with increasing lignocellulosic filler content is a typical result also obtained by other authors [52,94,111,144].…”

Improving fire behavior and smoke suppression of flame‐retardant PBS composites using lignin chelate as carbonization agent and catalyst

“…PBS (Trade name ECONORM1201) in pellet form, used as the matrix, was purchased from Fuwin New Material Co., Ltd, Shandong Province, China. It has a specific gravity at 25 C of 1.26 g/cm 3 and melt flow index (MFI) at 190 C/2.16 kg of 11 g/10 min. Lignin (M W = 9640 g mol À1 ; hydroxyl content: 3.9 mmol g À1 , measured by 31 P-NMR method according to 18 ) was purchased from Juntai Pulp & Paper Co., Ltd, Hunan Province, China.…”

“…PBS has already been widely used in many fields, such as agricultural films, biomedical materials, packing, and injection‐molded products 2 . More important is that PBS is expected to be ''all green'' in the future since the monomers can be obtained facilely by bacterial fermentation 3 . However, the inherent flammability and melt dripping upon burning extremely restrict the potential application of PBS, especially in foaming products, packing, and electric and electronic fields.…”

“…2 More important is that PBS is expected to be ''all green'' in the future since the monomers can be obtained facilely by bacterial fermentation. 3 However, the inherent flammability and melt dripping upon burning extremely restrict the potential application of PBS, especially in foaming products, packing, and electric and electronic fields. Therefore, it is necessary to modify PBS so that it can be used in areas where flame retardancy is required.…”

Biocomposites Based on Plasticized Wheat Flours: Effect of Bran Content on Thermomechanical Behavior

“…is often used as a basic ingredient. However, there is literature on the use of wheat flours to obtain bioplastics as an energetically and economically cheap alternative to purified starch [ 1 , 2 ]. Previous research from our group demonstrated that the tensile properties of thermoplastic films depended on wheat grain hardness and baking properties of refined flours [ 3 , 4 ].…”