Fabrication and properties of degradable PPC/EVOH/starch/CaCO₃ composites

Abstract

Thermally stable and biodegradable composites from poly (propylene carbonate) (PPC), poly (ethylene-co-vinyl alcohol) (EVOH), starch and CaCO₃ were fabricated by melt blending. Differential scanning calorimetry (DSC), differential thermal analysis/thermal gravimetric analysis (DTA/TGA), tensile test and scanning electron microscope (SEM) were performed to investigate the miscibility, thermal behavior and tensile properties of the PPC/EVOH/Starch/CaCO₃ composites. DSC results indicate that the introduction of EVOH could improve the compatibility between PPC and starch to some extent because of the interfacial interaction between PPC and EVOH, leading to an increase in tensile strength. The tensile strength began to decrease when more starch was added due to the aggregation of starch particles. SEM examination showed the good interfacial bonding between the fillers and polymeric components. The incorporation of both EVOH and fillers can greatly increase the thermal stability of PPC matrix. The PPC/EVOH/Starch/CaCO₃ composites can be melt processed and can be used as a common biodegradable material for a wide application.

Keywords

biodegradable / poly(propylene carbonate) / composites

References

[1] Zhang J. F., Sun X. Z. Mechanical Properties of Poly(lactic acid)/starch Composites Compatibilized by Maleic Anhydride[J]. Biomacromolecules, 2004, 5: 1 446-1 451.

[2] Du L. C., Meng Y. Z., Wang S. J., . Synthesis and Degradation Behavior of Poly(propylene carbonate) Derived from Carbon Dioxide and Propylene Oxide[J]. J. Appl. Polym. Sci., 2004, 92: 1 840-1 846.

[3] Chen X., Shen Z., Zhang Y. New Catalytic Systems for the Fixation of Carbon Dioxide. 1. Copolymerization of Carbon Dioxide and Propylene Oxide with New Rare-earth Catalysts-RE(P204)₃-Al(i-Bu)₃-R(OH)_n[J]. Macromolecules, 1991, 24: 5 305-5 308.

[4] Zhu Q., Meng Y. Z., Tjong S. C., . Thermally Stable and High Molecular Weight Poly(Propylene Carbonate)s from Carbon Dioxide and Propylene Oxide[J]. Polym. Int., 2002, 51: 1 079-1 085.

[5] Qin Z. Q., Thomas C. M., Lee S., . Cobalt-based Complexes for the Copolymerization of Propylene Oxide and CO₂: Active and for Polycarbonate Synthesis[J]. Angew. Chem. Int. Ed., 2003, 42: 5 484-5 487.

[6] Sugimoto H., Inoue S. Copolymerization of Carbon Dioxide and Epoxide[J]. J. Polym. Sci.: part A: Polym. Chem., 2004, 42: 5 561-5 573.

[7] Cohen C. T., Chu T., Coates G. W. Cobalt Catalysts for the Alternating Copolymerization of Propylene Oxide and Carbon Dioxide: Combining High Activity and Selectivity[J]. J. Am. Chem. Soc., 2005, 127: 10 869-10 878.

[8] Zhu Q., Meng Y. Z., Tjong S. C., . Catalytic Synthesis and Characterization of an Alternating Copolymer from Carbon Dioxide and Propylene Oxide Using Zinc Pimelate[J]. Polymer International, 2003, 52: 799-804.

[9] Ma X. F., Yu J. G., Wang N. Compatibility Characterization of Poly(lactic acid)/Poly(propylene carbonate) Blends[J]. J. Polym. Sci.: Part B: Polym. Phys., 2006, 44: 94-101.

[10] Xu J., Li R. K. Y., Meng Y. Z., . Preparation of Poly(propylene carbonate)/Organo-vermiculite Nanocomposites via Direct Melt Intercalation[J]. European Polymer Journal, 2005, 41: 881-888.

[11] Wang J. Z., Huang Y. H., Cong G. M. Mechanical Properties of Epoxy Resin Toughened by Polypropylene Carbonate[J]. Chinese Journal of Applied Chemistry, 1994, 11: 54-57.

[12] Li X. H., Tjong S. C., Meng Y. Z., . Fabrication and Properties of Poly(propylene carbonate)/Calcium Carbonate Composites[J]. J. Polym. Sci., Part B: Polym. Phy., 2003, 41: 1 806-1 813.

[13] Ha C. S., Ko M. G., Cho W. J. Miscibility of Nylon 46 and Ethylene-vinyl Alcohol Copolymer Blends[J]. Polymer, 1997, 38: 1 243-1 246.

[14] Lagaron J. M., Gimenez E., Saura J. J., . Phase Morphology, Crystallinity and Mechanical Properties of Binary Blends of High Barrier Ethylene-vinyl Alcohol Copolymer and Amorphous Polyamide and a Polyamide-containing Ionomer[J]. Polymer, 2001, 42: 7 381-7 394.

[15] Son T. W., Lim S. K. Physical Modification of Polypropylene. III. Novel Morphology of Polypropylene and Poly(ethylene-covinyl alcohol) with Epoxy Blend Fibers[J]. J. Appl. Polym. Sci., 1999, 73: 1 049-1 057.

[16] Lee S. Y., Kim S. C. Effect of Compatibilizer on the Crystallization, Rheological, and Tensile Properties of LDPE/EVOH Blends[J]. J. Appl. Polym. Sci., 1998, 68: 1 245-1 256.

[17] Du W. C., Zhong W. Space Charge Distribution and Crystalline Structure in Polyethylene Blended with EVOH[J]. Europ. Polym. J., 2004, 40: 1 987-1 995.

[18] Thiebaud S., Aburto J., Alric I., . Properties of Fatty-acid Esters of Starch and Their Blends with LDPE[J]. J. Appl. Polym. Sci., 1997, 65(4): 705-721.

[19] Park H. M., Lee R., Chowdhury S. R., . Tensile Properties, Morphology, and Biodegradability of Blends of Starch with Various Thermoplastics[J]. J. Appl. Polym. Sci., 2002, 86(11): 2 907-2 915.

[20] Ge X. C., Li X. H., Zhu Q., . Preparation and Properties of Biodegradable Poly(propylene carbonate)/Starch Composites[J]. Polymer Engineering and Science, 2004, 44(11): 2 134-2 140.

[21] Wang L., Li R. K. Y., Cao Y. X., . Essential Work of Fracture Analysis for Starch Filled Poly(propylene carbonate) Composites[J]. Materials & Design, 2007, 28(6): 1 934-1 939.

[22] Wang S. J., Tjong S. C., Du L. C., . Synthesis and Characterization of Alternating Copolymer from Carbon Dioxide and Propylene Oxide[J]. J. Appl. Polym. Sci., 2002, 85: 2 327-2 334.

[23] Wang X. L., Meng Y. Z., Li R. K. Y. Preparation and Properties of Biodegradable Polymeric Blends from Poly(propylene carbonate) and Poly(ethylene-co-vinyl alcohol)[J]. Journal of Biomedical Materials Research Part B, 2007, 83(2): 373-379.