共查询到19条相似文献,搜索用时 62 毫秒
1.
2.
3.
4.
5.
淀粉基生物降解塑料的研究进展 总被引:2,自引:0,他引:2
我国淀粉资源丰富、价格低廉,淀粉作为可完全生物降解的天然高分子材料日益受到人们的重视。本文综述了当今淀粉基生物降解塑料的分类、研究方法、发展状况,以及当今淀粉基生物降解塑料发展中存在的一些问题和应用前景。 相似文献
6.
新型淀粉基全生物降解薄膜的研究 总被引:2,自引:0,他引:2
以玉米淀粉为主要原料,研究了纳米SiO2改性淀粉薄膜的最佳分散处理工艺,并通过红外光谱、X-射线衍射和扫描电镜对该膜的结构进行了分析。结果表明:纳米SiO2的最佳分散工艺为2%纳米SiO2(占淀粉和聚乙烯醇干重)分散液中加入1.5%聚丙烯酰胺(PA)(指占纳米SiO2干重),先用机械力研磨分散1h,然后置入淀粉-聚乙烯醇(ST-PVA)共混液中;所制备的薄膜的各项性能均得到大幅度提高,其中拉伸强度可达34.82MPa,断裂伸长率为331%,达到国标GB4456-84所规定的标准;纳米SiO2在淀粉和聚乙烯醇分子间形成了均一致密的交联网状结构。该研究结果为纳米SiO2改性玉米淀粉制备一次性全生物降解薄膜,消除“白色污染”提供了一定的理论依据和实际应用参考。 相似文献
7.
以普通聚乙烯地膜为对照,研究了以玉米淀粉为主要原料制备的淀粉地膜的田艺特性。结果表明:淀粉地膜同普通PE地膜一样,具有保温、保水的作用,但淀粉地膜覆盖农作物后可在土壤中消失,对土壤无污染,消除残膜产生的“白色污染”,并对作物有增产作用。该研究结果为推广与应用淀粉地膜、消除残膜“白色污染”,提供了理论依据和实际参考。 相似文献
8.
9.
10.
11.
针对原有间歇式预张拉机钢丝绳两端抱紧装置压紧力小、人工操作劳动强度大、生产效率低等问题,设计新型间歇式预张拉机钢丝绳抱紧装置。采用电气配合液压传动方式,使抱紧装置压紧臂的各种动作实现自动化;根据钢丝绳规格结构、直径大小及所需的预张拉力,利用杠杆原理计算出最大抱紧力,从而确定抱紧装置的整体结构。实践结果表明:新型间歇式预张拉机钢丝绳抱紧装置结构紧凑简单,操作方便,生产效率高;压紧臂往复动作平稳,消除了人工操作由于压紧臂较大的冲击力对钢丝绳造成的损伤;减少故障停机率,维修成本大幅度降低。 相似文献
12.
目的 探究茜素的加入对马铃薯淀粉基复合膜理化性质的影响,并评估其氨响应行为。方法 以马铃薯淀粉为成膜基质,通过流延法制备淀粉基生物薄膜,并在其内部嵌入天然色素—茜素,制备茜素-马铃薯淀粉复合膜,通过紫外可见吸收光谱、傅里叶红外光谱等对复合膜的结构进行表征。结果 实验表明,添加3 mg/mL的茜素对复合膜的厚度、含水量、水接触角、化学和晶体结构均无明显影响,但显著改善了复合膜的光阻隔性能、拉伸强度、断裂伸长率和热稳定性。在实验室12 W LED T8节能灯正常发光条件下,复合膜对2500 mg/L的氨水表现出肉眼可见的由黄色到紫色的颜色转变,且茜素-马铃薯淀粉复合膜的氨响应行为在循环利用4次后并未表现出衰减。结论 茜素可有效改善马铃薯淀粉基复合膜的理化性能,并使复合膜表现出良好的氨响应行为,有潜力应用于高蛋白食品新鲜度的日光下可视化检测。 相似文献
13.
Using starch pellets as precursor for traditional edible food packaging for making thermoformed products is an excellent idea. We report here the complex water migration behaviour of starch pellets as influenced by plasticizer type and concentration at various temperatures. The evidence for synergistic interaction between plasticizers and water within starch is shown by the reduced effective moisture diffusivities and moisture migration fluxes at different overall plasticizer concentrations. In addition, the effective moisture diffusivities showed stronger dependence on moisture concentration and the plasticizer molecular weight even though the moisture flux was comparable. The drying process was characterized by two effective diffusion coefficients (D1, D2) and interestingly, the coefficients were an order of significance apart. Peleg model was investigated for predicting the drying behaviour and it is shown that the Peleg constants k1 and k2 increase with temperature. k2, a material structure parameter, showed variation by addition of plasticizers, indicating that plasticizers were able to modify fundamental structure; and xylitol showed greater average k2 values than glycerol. Further, k1, a moisture diffusivity parameter, was affected by temperature and Arrhenius relationship was used for activation energy values for k1 of plasticized starch. It is shown that compared to starch and water, presence of plasticizer had many order of significance higher k1 and confirm the hypothesis that plasticizers can ‘lock’ in water within the new structure. Xylitol showed better stability in controlling moisture diffusivities and migration fluxes as compared to glycerol. 相似文献
14.
15.
以不同厚度的聚四氟乙烯(PTFE)膜作为防水透湿膜,通过层压加工,分别对3种织物(纯棉织物、涤/棉织物和涤纶织物)进行防水透湿改性,制得3种具有防水透湿性能的复合织物(纯棉复合织物、涤/棉复合织物和涤纶复合织物)。探讨PTFE膜厚度及织物种类对复合织物的防水透湿性能的影响,结果表明:随着PTFE膜厚度增加,复合织物的透湿性和静水压会有所提高;PTFE膜厚度越小,复合织物的疏水性越好;PTFE膜厚度对复合织物的抗沾湿性能的影响较弱。就织物种类而言,涤纶复合织物的抗沾湿性能最好,沾水等级可达4级,水接触角最高为131.0°,具有良好的疏水性;纯棉复合织物的透湿率和静水压最高分别达5504 g/[m^2·(24 h)]和32.41 kPa,防水透湿性能优异,具有很好的应用前景。 相似文献
16.
17.
18.
In this work, it was evaluated the effect of moisture content on the structural and dielectric properties of cassava starch films by means of Fourier Transform infrared spectroscopy (FTIR), impedancimetric, and gravimetric analysis. The film samples were equilibrated in hermetically sealed desiccators, containing different saturated salts in water in order to promote activity of water between 0.11 and 0.85. The position and amplitude of the peaks in the “fingerprint” region of the FTIR spectra were changed due to the modifications in the interactions between the polymeric chains and water molecules. These effects may be related to the formation of semi‐crystalline regions in the film structure. The dielectric properties of the films were also strongly dependent on the moisture content, showing a non‐linear and a linear region, which was attributed to the domain of bound and free water in the film, respectively. The gravimetric analyzes showed the typical sigmoidal behavior, attributed to the way the water interacts with the biopolymer. Finally, the flexibility of the films increased with water content increasing. 相似文献