Biodegradable Green Composites from Distiller's Dried Grains with Solubles (DDGS) and a Polyhydroxy(butyrate-co-valerate) (PHBV)-Based Bioplastic
(1035–1045) Macromolecular Materials and Engineering 296 #11 (2011)
Zarrinbakhsh, Misra and Mohanty of the University of Guelph, Canada, producedbiodegradable green composites from distiller's dried grains with solubles (DDGS), a major coproduct of the corn ethanol industry, and a polyhydroxy(butyrate-co-valerate) (PHBV)-based bioplastic.  Green surface treatment of DDGS was performed and thermogravimetric analysis showed noticeable improvement in the degradation onset temperature of DDGS from 140 to 235 °C; this was a key point during melt processing of the composite. Utilizing compatibilizer improved the adhesion between DDGS and the matrix, which was observed by scanning electron microscopy. The green composite containing treated and compatibilized DDGS showed an enhanced modulus (by about 28% from 1.77 to 2.26 GPa) and an improved heat deflection temperature (by about 21% from 109 to 132 °C) compared to the polymeric matrix, while having tensile and flexural strengths equal to or greater than the respective properties of the matrix.  (RDC 11/3/2011)

Mechanical and viscoelastic properties of soybean oil thermoset reinforced with jute fabrics and carded lyocell fiber
(2855–2863)Journal of Applied Polymer  Science 122 #5 (2011)
Adekunl et al of the University of Borås,, Sweden, and Westsächsische Hochschule, Germany, produced composites and hybrid composites from renewable materials based on jute fibers, regenerated cellulose fibers (Lyocell), and thermosetting polymer from soybean oil. Three different types of jute fabrics with biaxial weave architecture but different surface weights, and carded Lyocell fiber were used as reinforcements. Hybrid composites were also manufactured by combining the jute reinforcements with the Lyocell. The Lyocell composite was found to have better mechanical properties than other composites. It has tensile strength and modulus of about 144 MPa and 18 GPa, respectively. The jute composites also have relatively good mechanical properties, as their tensile strengths and moduli were found to be between 65 and 84 MPa, and between 14 and 19 GPa, respectively. The Lyocell-reinforced composite showed the highest flexural strength and modulus, of about 217 MPa and 13 GPa, respectively. In all cases, the hybrid composites in this study showed improved mechanical properties but lower storage modulus. The Lyocell fiber gave the highest impact strength of about 35 kJ/m2, which could be a result of its morphology. Dynamic mechanical analysis showed that the Lyocell reinforced composite has the best viscoelastic properties.  (RDC 9/6/2011)

Mechanical and thermal properties of biocomposites from poly(lactic acid) and DDGS
(589–597)Journal of Applied Polymer  Science 121 #1 (2011)  
Li and Sun of Kansas State University, Kansas, developed low-cost, high-performance biodegradable composites by thermal compounding of distillers dried grains with solubles (DDGS)  and polylactic acid (PLA) with methylene diphenyl diisocyanate (MDI) as a coupling agent.  The PLA/20% DDGS composite with 1% MDI showed tensile strength (77 MPa) similar to that of pure PLA, but its Young's modulus was 25% higher than that of pure PLA. With MDI, strong interfacial adhesion was established between the PLA matrix and DDGS particles, and the porosity of the composites decreased dramatically. Crystallinity of PLA in the composites was higher than that in pure PLA. Composites with MDI had higher storage moduli at room temperature than pure PLA. This novel application of DDGS for biocomposites has significantly higher economic value than its traditional use as a feedstuff.  (RDC 4/14.2011)

Mechanical properties of 1,2,4,5-benzene tetra carboxylic chitosan-filled chitosan biocomposites
(111–126)Journal of Applied Polymer  Science 121 #1 (2011)
Julkapli, Ahmad and Akil of the Universiti Sains Malaysia, Malaysia, used 1,2,4,5-benzene tetra carboxylic chitosan (BTC) as a filler to reinforce a chitosan matrix (Cs).  Introduction of BTC filler (at 0, 2, 4, 6, 8, and 10 wt%) provided dramatic increments in σR and E values, but the observed values of εR and K correlated negatively to similar levels of BTC filler. Morphological results demonstrate that the breaking surfaces of biocomposites form rugged deformation lines, resulting in high σK values of the biocomposites   (RDC 4/14/2011)

Performance and biodegradability of a maleated polyester bioplastic/recycled sugarcane bagasse system
(427–435)Journal of Applied Polymer  Science 121 #1 (2011)
Wu of Kao Yuan University, China, studied composites of poly(butylene succinate adipate) (PBSA) and recycled sugarcane bagasse (SCB) were evaluated.  Composites containing maleic anhydride (MA)-grafted PBSA (PBSA-g-MA/SCB) showed noticeably superior mechanical properties because of greater compatibility between the two components. The dispersion of SCB in the PBSA-g-MA matrix was highly homogeneous as a result of ester formation between the carboxyl groups of PBSA-g-MA and hydroxyl groups in SCB and the consequent creation of branched and crosslinked macromolecules. Each composite was subjected to biodegradation tests in a Rhizopus oryzae compost. Morphological observations indicated severe disruption of film structure after 60 days of incubation, and both the PBSA and the PBSA-g-MA/SCB composite films were eventually completely degraded. The PBSA-g-MA/SCB films were more biodegradable than those made of PBSA and exhibited a higher intrinsic viscosity, implying a strong connection between these characteristics and biodegradability.  (RDC 4/14/2011)