• Polymer(Korea)
• /
• v.29 no.6
• /
• pp.557-564
• /
• 2005

Thermoplastic starch (TPS) was manufactured and blended with poly(butylene adipate-co-succinate) (PBAS), which is one of the most popular biodegradable aliphatic polyesters. The effects of the TPS contents on the mechanical properties, thermal characteristics, and biodegradability of PBAS/TPS blends were investigated. The foaming characteristics of those were also studied. With small amount of TPS, mechanical properties of the blends were largely deteriorated and the variations of them decreased with more addition of TPS. In addition, TPS decreased crystallinity and thermal decomposition temperature of PBAS. The PBAS/TPS foam having maximum blowing ratio was obtained with 20 Phr of TPS, and their blowing ratio decreased with the further increase of TPS.

• Polymer(Korea)
• /
• v.24 no.1
• /
• pp.48-57
• /
• 2000

Polycaprolactone (PCL) and thermoplastic starch (TPS) blends were prepared. Mechanical properties, thermal property, water absorption, biodegradability by composting and surface morphology of PCL/TPS blends were investigated. The compositions of PCL/TPS blends were 90/10, 80/20, 70/30, 60/40, 50/50, 40/60, 30/70, 20/80, and 10/90. Strength and elongation at break decreased as the content of TPS increased, while modulus increased. DSC thermogram of TPS showed two glass transition temperatures (T$_{g}$ ) at 23$^{\circ}C$ and 126$^{\circ}C$. And TPS proved to be an amorphous polymer because there was no endothermic peak due to the melting of starch crystal. The unchanged melting temperatures and T$_{g}$ 's of PCL/TPS blends revealed that PCL and TPS were not miscible. All of the blends were found to be mechanically compatible but phase separated in each other. After 45 days composting, the biodegradability of PCL was 44% and that of PCL/TPS blends increased as the contents of TPS increased.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.6
• /
• pp.21-26
• /
• 2018

Thermoplastic starch (TPS) was prepared by mixing starch with glycerol as a plasticizer. The glycerol content ranged from 20 to 35 wt. % and TPS was prepared in a twin screw extruder. The shear viscosity, thermal and mechanical properties of the TPS were investigated. The viscosity of TPS exhibited typical shear thinning behavior: decreasing viscosity with increasing shear rate. The power index, n, increased with increasing glycerol content. This is because as the content of glycerol, a Newtonian fluid, increases, the viscosity behavior of the TPS becomes closer to that of a Newtonian fluid. The thermal behavior of TPS showed that starch and glycerol are miscible. In addition, when TPS was aged for more than one day at room temperature, TPS showed a partially miscible phase structure. The moisture absorbed into the TPS was assumed to change the phase behavior. The mechanical properties of TPS were found to be strongly dependent on the content of the plasticizer. Both the toughness and stiffness increased with increasing plasticizer content. DSC showed that this unusual result was due to the combined effect of humidity and the high amylose content in starch.

• Polymer(Korea)
• /
• v.26 no.1
• /
• pp.145-151
• /
• 2002

Thermoplastic starch(TPS) was prepared from mixing starch and glycerol by twin extruder. The blends were then prepared from high density polyethylene(HDPE) and TPS. Mechanical properties, thermal properties, and morphology of the blends were investigated. Their biodegradability was also studied by using aerobic composting method(ISO14855). Tensile strength, modulus and elongation at break decreased as the content of TPS increased. In particular elongation at break decreased rapidly even at the lower content of TPS. The melting temperatures of the blends were not changed, which showed that HDPE and TPS were immiscible. The morphology of the fractured surface of blend films was investigated by scanning electron microscopy(SEM). It was found that phases were separated. After composting for 45days, the biodegradability of the blends increased as the content of TPS increased.

• Journal of Environmental Science International
• /
• v.22 no.10
• /
• pp.1287-1294
• /
• 2013

In this study, thermoplastic starch (TPS), cross-linked starch (CS), and cross-linked starch modified with glycerol (CTPS) were prepared, and the mechanical properties of the compatibilized low-density polyethylene (LDPE) blends (LDPE/TPS, LDPE/CS, and LDPE/CTPS) were investigated and compared with those of uncompatibilized LDPE/TPS, LDPE/CS, and LDPE/CTPS blends. Maleic-anhydride-grafted polyethylene was used as the compatibilizer. The enhanced tensile strength and elongation at break for the compatibilized LDPE/modified starch blends are a result of the improved compatibility between LDPE and the modified starch, which was confirmed by torque measurements and scanning electron microscopy.

• Proceedings of the Korean Fiber Society Conference
• /
• 2002.04a
• /
• pp.289-292
• /
• 2002

전분을 이용한 환경친화성 고분자 플라스틱 재료에는 전분충진형, blend형 등이 있으나, 대체로 전분은 보조재료로 사용된다. 이에 반해 extruder를 이용한 전분발포체나 TPS (Thermoplastic starch) 등은 전분을 주재료로 사용하여 플라스틱 재료를 만드는 것이지만, TPS 필름의 Tg가 실온보다 높아 glassy 상태의 brittle한 성질로 인해 물성이 낮으며, 수분 친화적인 성질로 인해 플라스틱 재료로서의 사용이 제한되는 단점이 있다[1,2]. (중략)