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材料生物降解能力评价方法的研究 总被引:2,自引:1,他引:1
采用纤维素、淀粉、聚羟基丁酸酯(polyhydroxybutyrate,PHB)、聚羟基丁酸/戊酸酯[poly(hydroxybutyratecohydroxyvalerate),PHBV]、聚乙烯/淀粉共混物和聚乙烯等6种试验材料,在可控堆肥条件下通过测定释放的二氧化碳的方法,以及在水性培养液中需氧条件下分别通过测定氧气消耗量和释放的二氧化碳的方法,测定材料的生物分解能力。结果表明3种方法测得的材料生物降解百分率(%)分别依次为:纤维素(76.9)>淀粉(74.3)>PHB(73.3)>PHBV(70.5)聚乙烯/淀粉共混物(20.3)聚乙烯(0.3);PHB(78.7)>PHBV(71.2)>纤维素(70.7)聚乙烯/淀粉共混物(24.4)聚乙烯(0.3);PHB(73.6)>PHBV(72.4)>纤维素(71.9)聚乙烯/淀粉共混物(26.2)聚乙烯(0.2),在评价聚合物生物降解能力上基本具有等效性。 相似文献
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可生物降解聚合物中的层状硅酸盐纳米复合材料,可极大提高其力学性能,但同时会影响到材料的降解速率。研究纳米填料对可生物降解聚合物降解速率的影响及降解机理的变化,可拓宽其应用领域。综述聚乳酸(PLA)、淀粉、聚己内酯(PCL)、纤维素、聚羟基烷脂肪酸酯(PHA)、聚琥珀酸丁二醇酯(PBS)等可生物降解聚合物基层状硅酸盐纳米复合材料制备及降解性能研究现状及进展。 相似文献
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乙酰化淀粉/聚己内酯共混物的制备和性能研究 总被引:7,自引:0,他引:7
分别采用淀粉(TPS)、乙酰化淀粉(TPAS)与聚己内酯(PCL)进行熔融共混,制备了可生物降解的塑料,探讨了淀粉乙酰化改性后对共混物力学性能、耐水性、熔融流动性、相容性及生物降解性的影响。共混物的拉伸强度均随PCL用量的增加而增大,TPAS/PCL体系的拉伸强度低于TPS/PCL体系,而断裂伸长率高于TPS/PCL体系。PCL可以明显改善淀粉基材料的耐水性,淀粉乙酰化后共混体系的相容性及熔体流动性得到一定的改善,生物降解性略微下降。 相似文献
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Byung Seon Yoon Moon Ho Suh Shi Hwa Cheong Jae Eue Yie Sung Hwa Yoon Suck Hyun Lee 《应用聚合物科学杂志》1996,60(10):1677-1685
Three degradable polymer materials such as starch–polyethylene (PE) binary blends, PE containing starch and a photoactivator, and PE containing starch and a photoactivator which was coated with gelatin were prepared and their degrees of photodegradation and/or photodegradation after biodegradation were investigated. The addition of the gelatin-coated ferric salt in PE extended the induction period of degradation and accelerated pho-todegradation after the removal of coating material by biodegradation. This result suggested that the degradation rate of PE could be controlled if more powerful photoactivators and/or coating material are developed and their contents are optimized. © 1996 John Wiley & Sons, Inc. 相似文献
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C. S. Tena-Salcido F. J. Rodríguez-González M. L. Méndez-Hernández J. C. Contreras-Esquivel 《Polymer Bulletin》2008,60(5):677-688
In this study, thermoplastic starch (TPS) was mixed with low density polyethylene with different melt
flow indexes in a one-step extrusion process to produce LDPE/TPS blends varied from 32% to 62% by weight
of TPS. The influence of starch content and LDPE viscosity on morphology, biodegradation and tensile properties
of LDPE/TPS blends were evaluated. Starch continuity and biodegradability were studied by hydrolytic, enzymatic
and bacterial degradation. The LDPE viscosity had a considerable effect on the morphology and the connectivity
of the starch particles. Evaluation of hydrolytic extraction showed that blends having TPS content above
50 wt% possessed a full connectivity. Studies of biodegradation indicated that the bacterial attack on
starch resulted in weight loss of TPS of 92%, 39% and 22%, for PE1/TPS having 62% and 32% TPS, and PE2/TPS
(31% TPS), respectively. Comparatively, the weight loss was more significant at 100%, 66% and 31% by hydrolytic
extraction. Differences between these two techniques were discussed in terms of the accessibility of starch
domains to microorganisms. Tensile properties (εb and E) decreased with increasing
exposure time to activated sludge. Changes in tensile properties were highly dependent on the biodegradation
rate. PE1/TPS blends having 32% starch remained ductile after 45 days of exposure to bacterial attack. 相似文献
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The effects of the starch content, photosensitizer content, and compatibilizer on the photobiodegradability of low‐density polyethylene (LDPE) and banana starch polymer blend films were investigated. The compatibilizer and photosensitizer used in the films were PE‐graft‐maleic anhydride (PE‐g‐MA) and benzophenone, respectively. Dried banana starch at 0–20% (w/w) of LDPE, benzophenone at 0–1% (w/w) of LDPE, and PE‐g‐MA at 10% (w/w) of banana starch were added to LDPE. The photodegradation of the blend films was performed with outdoor exposure. The progress of the photodegradation was followed by determining the carbonyl index derived from Fourier transform IR measurements and the changes in tensile properties. Biodegradation of the blend films was investigated by a soil burial test. The biodegradation process was followed by measuring the changes in the physical appearance, weight loss, and tensile properties of the films. The results showed that both photo‐ and biodegradation rates increased with increasing amounts of banana starch, whereas the tensile properties of the films decreased. The blends with higher amounts of benzophenone showed higher rates of photodegradation, although their biodegradation rates were reduced with an increase in benzophenone content. The addition of PE‐g‐MA into polymer blends led to an increase in the tensile properties whereas the photobiodegradation was slightly decreased compared to the films without PE‐g‐MA. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2725–2736, 2006 相似文献
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Patrice Dole Luc Avrous Catherine Joly Guy Della Valle Christophe Bliard 《Polymer Engineering and Science》2005,45(2):217-224
Adhesion tests performed on various plasticized starch‐polyethylene multi‐layer systems led to the selection of a suitable combination of polymers compatible with the starch‐based layer. The compatibility of starch and polyethylene was better achieved through maleic anhydride functionalized polyethylene (PEg) than chemically modifying starch. The PEg method proved efficient provided that the water content, and the plasticizer nature and contents of the starch layer were carefully chosen. Computed shear viscosity allowed us to select a suitable botanical origin of starch such that the interfacial instabilities of the coextrusion process were minimized. The use of a multilayer structure (PE/PEg/starch/PEg/PE) improved gas barrier properties at high relative humidity. The higher quantity of water sorbed by thermoplastic starch (as compared to EVOH) coupled with starch's specific water sorption isotherm lengthened the water equilibration time in the hydrophilic inner layer significantly. As a result the gas barrier properties of the starch based multiplayer systems were enhanced as compared to existing commercial multiplayer systems (PE/PEg/EVOH/PEg/PE). This specific “water‐buffering property” of the starch inner layer should prove useful in packaging applications of perishables with extended shelf life in environments of varying relative humidity. Polym. Eng. Sci. 45:217–224, 2005. © 2005 Society of Plastics Engineers. 相似文献
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Summary The use of biodegradable polymers has provided an alternative to the problem of polymer-based products discarded in the environment. Poly(ε-caprolactone) (PCL) is a biodegradable polymer that has been used industrially, but it is very expensive. Starch is a potentially useful material for biodegradable plastics because of its natural abundance and low cost. The aim of this work was to examine the effect of adding azodicarbonomide (ADC) as an expansor to blends of PCL with corn starch. Different proportions, of ADC (0.1%, 0.2% and 0.3%, w/w) were added to pure PCL and to PCL/starch (50/50) blends and their properties were studied. Biodegradable blends of PCL with starch had a higher density than PCL alone and the addition of ADC reduced the density of the materials. The incorporation of starch increased the water absorption and ADC did not significantly alter this property. The incorporation of starch into PCL reduced the tensile strength and the elongation at break; ADC enhanced these reductions and also decreased the Young’s modulus of PCL. SEM showed that blends prepared with starch were immiscible, had a homogeneous dispersion of starch, and poor interfacial adhesion. The addition of ADC resulted in cells in the interior of the polymers. The 50/50 PCL/starch blends biodegraded faster than PCL, and ADC had no significant influence on the biodegradation of the blends but inhibited the biodegradation of PCL. 相似文献
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Thermoplastic starch (TPS), as opposed to dry starch, is capable of flow and hence when mixed with other synthetic polymers can behave in a manner similar to conventional polymer-polymer blends. This paper presents an approach to preparing polyethylene/thermoplastic starch blends with unique properties. A one-step combined twin-screw/single screw extrusion setup is used to carry out the melt-melt mixing of the components. Glycerol is used as the starch plasticizer and its content in the TPS is varied from 29 to 40%.Under the particular one-step processing conditions used it is possible to develop continuous TPS (highly interconnected) and co-continuous polymer/TPS blend extruded ribbon which possess a high elongation at break, modulus and strength in the machine direction. The PE/TPS (55:45) blend prepared with TPS containing 36% glycerol maintains 94% of the elongation at break and 76% of the modulus of polyethylene. At a composition level of 71:29 PE/TPS for the same glycerol content, the blend retains 96% of the elongation at break and 100% of the modulus of polyethylene. These excellent properties are achieved in the absence of any interfacial modifier and despite the high levels of immiscibility in the polar-nonpolar TPS-PE system. The 55:45 blend possesses a 100% continuous or fully interconnected TPS morphology, as measured by hydrolytic extraction. This highly continuous TPS configuration within the blend should enhance its potential for environmental biodegradation. The elongation at break in the cross direction of these materials, although lower than the machine direction properties, also demonstrates ductility at high TPS concentrations. At a glycerol content of 36% in the TPS, the blends demonstrate only very low levels of sensitivity to moisture. A high degree of transparency is maintained over the entire concentration range due to the similar refractive indices of PE and TPS and the virtual absence of interfacial microvoiding.Effective control of the glycerol content, TPS concentration and processing conditions can result in a wide variety of morphological structures including spherical, fiber-like, highly continuous and co-continuous morphologies. These various blend morphologies are shown to be the determining parameters with respect to the observed mechanical properties.This material has the added benefit of containing large quantities of a renewable resource and hence represents a more sustainable alternative to pure synthetic polymers. 相似文献
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Emmanuelle‐Anita‐Claude Demengeot Inga Baliutaviciene Jolita Ostrauskaite Liudvikas Augulis Violeta Grazuleviciene Lina Rageliene Juozas Vidas Grazulevicius 《应用聚合物科学杂志》2010,115(4):2028-2038
The different natural oils epoxidized with 3‐chloroperbenzoic acid were crosslinked with diepoxy reactive diluents, bisphenol A propoxylate diglycidyl ether, and 3,4‐epoxycyclohexylmethyl‐3,4‐epoxyclohexane‐carboxylate, using cationic initiator at 60°C and photoinitiators at the room temperature. The insoluble fraction of the polymeric products was 59–90%. The Young modulus of the crosslinked polymer films ranged from 2 to 861 MPa. The 10% weight loss temperatures of the crosslinked polymers estimated by thermogravimetric analysis were in the range from 250 to 420°C. The water vapor transmission rate of the crosslinked biopolymer films ranged from 6 to 49 g/m2/24 h. Biochemical oxygen demand and biodegradation in soil of the crosslinked polymers were studied. The crosslinked polymers showed higher biodegradation rate than cellulose, starch, and polyvinylalcohol. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献