Water resistance, mechanical properties, and biodegradability of poly(3‐hydroxybutyrate)/starch composites

Abstract

Composites of poly(3-hydroxybutyrate), P(3HB), and starch were prepared by solution casting technique. To improve adhesion of starch to P(3HB), stearic acid was added as a compatibilizer and glycerol as a plasticizer. The water resistance, mechanical, and biodegradable properties of the P(3HB)/starch composites were studied. Diffusion and penetration coefficients of water increased with increasing starch content in the composites. The results showed that the elastic modulus and strain at rupture of the P(3HB)/starch composites were enhanced by increasing starch content upto 10 wt % and the tensile strength increased from 21.2 to 93.9 MPa. The presence of starch content higher than 10 wt % had an adverse effect on the mechanical properties of the investigated composites. The biodegradation rate using Actinomycetes increased proportionally to the starch content in the composite and accelerated in a culture medium of pH % 7.0 at 30 C. Enzymatic degradation experiments showed that lipase produced by Streptomyces albidoflavus didnot degrade P(3HB)/starch composites.

Poly(butylene succinate -co- butylene adipate)/cellulose nanocrystal composites modified with phthalic anhydride

“…Less water absorption of polymers will reduce mold erosion, and slow down the material degradation rate (Ismail, & Gamal, 2010). The water absorption and penetration performance are also important for a biomass material (Araujo, Cunha, & Mota, 2004).…”

Structure–property relationships of reactively compatibilized PHB/EVA/starch blends

“…In recent years, the interest is focused on blending of starch with other biocompostable materials such as PHB (Don, Chung, Lai, & Chiu, 2010;Ismail & Gamal, 2010;Magalhães, Dahmouche, Lopes, & Andrade, 2013;Reis et al, 2008;Xiong et al, 2013 the biocompostability and renewability. Whereas, the properties of PHB/starch blends are poor due to a lack of affinity between the two components (Reis et al, 2008).…”

“…Whereas, the properties of PHB/starch blends are poor due to a lack of affinity between the two components (Reis et al, 2008). Although poly(vinyl acetate) (Don et al, 2010), nano-clay (Ismail & Gamal, 2010), peroxide (Avella, Errico, Rimedio, & Sadocco, 2002) and PHB-g-acrylic acid (Liao & Wu, 2007) could enhance the affinity between PHB and starch, the toughness of their blends was only improved to a certain extent.…”

The role of dicumyl peroxide in the preparation of chloroprene rubber/starch/sodium acrylate water-swellable composites

“…2 shows that mass loss ratio decreased from 10.6% to 4.1% with increasing DCP amount from 0 to 2.25 phr. This is an interesting result, considering that the mass loss ratio generally increases with the increase of water swelling ratios (Ismail & Gamal, 2010;Liu et al, 2006;Zhang, He, Zou, & He, 2004). These unexpected observations can be understood by the fact that DCP could initiate the polymerization of acrylic acid salt (Ren et al, 2005).…”