Polycaprolactone thermoplastic starch

A wide range of thermoplastic starch compounds have been claimed in recent years. Formulations of thermoplastic starch with linear, biodegradable polyesters, including polycaprolactone and PHBV,174 176 and with polyamides175 have been reported. Laminated structures have been claimed using thermoplastic starch or starch blends as one or more of the layers.175,177,178 The use of polymers latexes as components of thermoplastic starch blends has also been claimed.179 181 Blends with natural polymers are also claimed, including cellulose esters182,183 and pectin.184 A crosslinked thermoplastic material of dialdehyde starch and protein has been reported.185... 

Reactive blending of thermoplastic starch/polymer blends has been examined recently and aims to increase properties and performance via control of blend morphologies. Mani [58, 59] examined different techniques for compatibilising starch-polyester blends. They examined development of maleic anhydride grafted polyester/starch blends and starch-g-polycaprolactone... 

Other biodegradables include aliphatic polyesters, polycaprolactones, and thermoplastic starch [61]. 

Kenaf Dust Polycaprolactone/thermoplastic sago starch [37]... 

A. Taghizadeh, B.D. Favis, Carbon nanotubes in blends of thermoplastic starch/ polycaprolactone, in Annual Technical Conference - ANTEC, Conference Proceedings, vol. 1, 2012, pp. 126-131. 

Different compositions of wheat thermoplastic starch (TPS) and polycaprolactone (PCL) were melt blended by extrasion and injected [104]. It was noticed that the addition of PCL to the TPS matrix allowed the weakness of pure TPS to be overcome low resilience, high moisture sensitivity and high shrinkage, even at low PCL concentrations, e.g. 10 wt%. However, a fairly low compatibility between both polymeric systems was reported. For PCL-based blends, mechanical properties depend both on plasticization level and PCL content (Table 3.22). 

Sarazin P, Li G, Orts WJ, Favis BD (2008) Binary and ternary blends of polylactide, polycaprolactone and thermoplastic starch. Polymer 49(2) 599-609... 

Among the most important biodegradable polymers, we can specially mention thermoplastic starch (TPS), polylactide (PLA), polycaprolactone (PCL), and polyhydroxybutyrate and polyhydroxyalkanoate (PHA) due to their promising properties. 

Polycaprolactone can increase the tensile strength and impact strength but reduce the ultimate elongation, tensile modulus, and shrinkage of the thermoplastic starch (TPS) polymer (Avemous et al. 2000). Montmorillonite clay can improve the properties of TPS and create a biobased nanocomposite (Bordes et al. 2009 Aouada et al. 2011). 

FIGURE 19 Representative composting time (in months) of biopolymers (TPS - Thermoplastic starch, PC - Polycaprolactone, mc-PHA - medium chain length PHA, Al-co-PEs -Ahphatic co-polyester, PEA - Polyester amides, Ah/arocoPEs - Aliphatic/aromatic copolyester, and CDAc - Cellulose diacetate). 

Shin BY, Lee SI, Shin YS, Balakrishnan S, Narayan R. Rheological, mechanical and biodegradation studies of blends of thermoplastic starch and polycaprolactone. Polym Eng Sci 2004 44 1429-38. 

Agricultural polymers (polysaccharides or proteins) can be extracted and eventually purified. They can be used alone or in a mixture with a synthetic biodegradable polymer such as polycaprolactone or other synthetic biodegradable polyesters (e.g. blends of thermoplastic starch and polyesters). 

Averous L., Moro L., Dole R, Fringant C., Properties of thermoplastic blends Starch-polycaprolactone, Polymer, 41, 2000, 4157-4167. 

In mid-1970, due to the petroleum crisis, the production of plastics from renewable resources became economically attractive (Lenz and Marchessault 2005). The price of an oil barrel increased at very high values, and the same occurred to all petroleum products. So, at that time, an extensive search of materials that could replace synthetic polymers took place. Many polymers were proposed and investigated regarding to its biodegradability and its possibility of industrial application, such as cellulose, starch, polycaprolactone, poly(lactic acid), and PHA. Among these polymers, PHA are of particular interest due to their biodegradability, biocompatibility, and mainly because of their similarity to conventional thermoplastics (Zinn et al. 2001). 

Avernous, L., Moror, L., Dole, P., and Fringant, C., (2000) Properties of thermoplastic blends starch-polycaprolactone. Polymer, 41 4157-4167. 

Otey, F. H., Mark, A. M., Mehltretter, C. L., and Russell, C. R., 1974, Starch-based film for degradable agricultural mulch. Ind. Eng. Chem., Prod. Res. Develop. 13 90-92. Averous, L., Moro, L., Dole, P., and Fringant, C., 2000, Properties of thermoplastic blends starch-polycaprolactone. Polymer 41 4157-4167. 

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