豌豆淀粉/聚乳酸双层膜的制备与性能表征

采用溶液流延法以豌豆淀粉（PS）和聚乳酸（PLA）为原料制备了豌豆淀粉/聚乳酸（PS/PLA）双层薄膜。通过对双层薄膜的吸水性、溶解性、水蒸气透过性、拉伸性能、表面形貌等进行测试,研究了薄膜的力学性能、疏水性能以及水蒸气阻隔性能。结果表明：随着双层膜中聚乳酸层的比例增加,双层薄膜的吸水性、溶解性和水蒸气透过性逐渐降低,拉伸强度和拉伸模量逐渐增加,断裂伸长率逐渐下降,表明水蒸气阻隔效果明显,增加了膜的韧性,降低了膜的强度。当PLA和PS的质量比为50：50时,PS/PLA双层膜的拉伸强度为（13.47±0.75）MPa,拉伸模量为（0.848±0.002）GPa;断裂伸长率为（16.11±0.16）%,水蒸气透过系数为0.27×10^-10 g·cm/（cm²·s·Pa）。     

改性淀粉在滚筒干燥设备生产中的应用研究

考察了滚筒干燥设备的淀粉布料量、蒸汽压力、滚筒转速等参数对淀粉糊化度和溶解时间的影响,优化了改性淀粉生产中滚筒干燥过程的工艺,制备的交联氧化羧甲基化淀粉的黏度、冻融稳定性、黏结力、耐热及耐剪切性增强;经胶液制备实验和干黏性分析表明:产品的冷热溶解性、分散性、吸水性以及黏附纸破率等指标明显提升。     

柠檬酸改性聚乙烯醇制备可生物降解膜的研究

选择柠檬酸（CA）作为单体在聚乙烯醇（PVA）水溶液中制备柠檬酸改性的聚乙烯醇交联聚合物,并用红外光谱表征膜的结构：重点考察了反应时间和反应温度对柠檬酸改性聚乙烯醇键合度的影响;使用淀粉与聚乙烯醇交联聚合物共混,制备了柠檬酸改性聚乙烯醇（CA—SP）,并将其延流成膜,采用溶菌酶体外降解实验,测定CA—SP膜的降解性能,与柠檬酸键合量对生物降解的影响。测试了降解的CA—SP膜的力学性能考察。结果表明：柠檬酸的多羧基结构,能与PVA的羟基发生酯化,从而改性淀粉／聚乙烯醇（SP）;在60℃下,反应3h时,柠檬酸的键合量可达到最大,为3．92g/g。使用溶菌酶对其进行降解,通过降解的失重率测定,发现柠檬酸的键合量越高,膜降解性能越好。柠檬酸改性的SP膜几乎可以达到完全降解。     

交联剂的用量对淀粉-壳聚糖-聚乙烯醇-明胶共混膜的性能影响

本文研究了交联剂对淀粉/壳聚糖/聚乙烯醇/明胶共混膜的透光性、透气性、吸水性及保水性和力学性能的影响。结果表明：共混膜的性能与交联剂有较大关系。在交联剂用量在0%~5%的范围内,随着交联剂用量的增加,共混膜的扯断伸长率、吸水性和保水性随之降低,共混膜的拉伸强度、撕裂强度、透水气性和透光性先增加后减小。     

中国塑料专利

利用粉磨机械力化学方法改性淀粉的方法显著改变了淀粉颗粒形貌，并使其微细化，甚至达到亚微米级，改变了淀粉的糊化性质、流变性质等，并赋予淀粉溶解性好、吸水性高、生物反应活性灵敏及具有低粘高固形物糊体系等特殊性质。     

壳聚糖季铵/明胶共混抗菌膜的性能研究

壳聚糖季铵盐是壳聚糖的衍生物,因其具有良好的水溶性、抗菌性、吸湿保湿性以及絮凝性等特点而被应用于诸多领域。本文以明胶和壳聚糖季铵盐膜材料制备了共混抗菌膜,研究了混合体系中壳聚糖季铵盐与明胶配比及壳聚糖季铵盐浓度对共混抗菌膜机械性能、透光性和热稳定性的影响,利用FTIR分析了混合体系中分子间的作用力。结果表明,随着壳聚糖季铵盐含量的增加,共混膜的拉伸强度逐渐降低,断裂伸长率明显增加且共混膜的热稳定性降低。同时,共混膜对大肠杆菌和金黄色葡萄球菌均具有良好的抗菌性。     

国外有关塑料助剂研究的期刊文摘

正纤维素纳米纤维增强的淀粉纳米复合物的生物降解和机械性能(Carbohydrate polymers,2015,1321-8)本项研究评估了化学改性的纤维素纳米纤维(CNFs)在增强热塑性淀粉(TPS)纳米复合物的生物降解性能和机械性能的作用。CNFs首先用乙酐进行改性,而淀粉纳米复合物采用溶剂浇注法用玉米淀粉和甘油/水作为增塑剂,混合10%重量比的CNFs或乙酰化CNFs(ACNFs)制得。对获得的纳米复合物的微观形貌、吸水性(WA)、水     

淀粉对水转印用PVA膜的改性研究

以聚乙烯醇1788(PVA)作为原料,以丙三醇为增塑剂,加入0%~2.5%的淀粉,对水转印PVA膜进行了改性研究。结果表明,加入淀粉后,PVA溶液的粘度增大,膜的溶解时间变长,水上伸长率变小,含水率变小,扯断强度增强,形变缩小;通过膜表面观察,发现淀粉在膜中以聚集颗粒状态存在。研究发现,在淀粉加入PVA后使水转印膜的水溶性得到很大改善。     

湿相分离法壳聚糖膜的结构与性能研究

采用湿相分离法制备壳聚糖膜。主要研究成型条件对壳聚糖膜力学性能和膜的形态结构的影响。结果表明,用氢氧化钠和无水硫酸钠的双组分凝固浴可获得具有良好的力学性能和内部结构的壳聚糖膜。当双组分凝固浴浓度为6%NaOH-1.2%Na2SO4,凝固时间为6 h时,制得的壳聚糖膜的拉伸强度可达到12.44 MPa。经过交联改性可以进一步提高壳聚糖膜的机械性能并改善其内部结构。     

湿法聚乙烯锂电隔膜敏化辐射交联效应与性能研究

聚乙烯锂电隔膜利用三羟甲基丙烷三丙烯酸酯(TMPTA)白油分散液进行溶胀,然后电子束辐照。15 k Gy辐照剂量下,改变TMPTA浓度(质量分数),这样能显著提高聚乙烯锂电隔膜的抗穿刺力及机械性能。3%TMPTA浓度下,随着电子束辐照剂量的增加,聚乙烯锂电隔膜性能发生明显变化。3%TMPTA、10 k Gy时抗穿刺力最大为4. 03 N,极限拉伸强度135. 76 MPa。该发现对提高锂电池抵抗锂枝晶穿透锂电隔膜能力有重要意义。     

Heterogeneous method of chitosan film preparation: Effect of multifunctional acid on film properties

The heterogeneous crosslinking method was applied to chitosan films with citric acid to observe and understand the effect of a multifunctional acid at a low concentration on film properties. Neat and neutralized chitosan films and films containing 15% (w/w) citric acid (denoted as CA films) were characterized by mechanical, water vapor permeability (WVP), and thermogravimetric analysis tests. The CA films displayed a higher tensile strength by 10%, lower WVP by 30%, and higher thermal stability, compared to neutralized films. The crystalline structure converted back from tendon to Type II after the addition of citric acid, as determined by X-ray diffraction. Neat films displayed a lower water contact angle (72°) compared to neutralized and CA films (78°–79°). The heterogeneous method was also applied to incorporate a plasticizer into a neutralized film to potentially observe the glass transition using dynamic mechanical analysis. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48648.     

柠檬酸改性对变色聚乙烯醇流延膜性能的影响

以聚乙烯醇（PVA）为母液、柠檬酸为交联剂制备了变色PVA流延膜,并对薄膜的力学性能、光学性能和热稳定性进行了研究。结果表明,随着柠檬酸质量分数的增大,薄膜的抗张强度增大,伸长量减小;随着柠檬酸质量分数的增加,薄膜的雾度呈上升趋势;柠檬酸质量分数对变色薄膜的颜色及颜色变化也有较大影响;添加柠檬酸提高了薄膜的热分解温度,从而提高了薄膜的热稳定性。     

Composition optimization of polyvinyl alcohol/rice starch/silk fibroin‐blended films for improving its eco‐friendly packaging properties

Biopolymers obtained from renewable sources have been exploited in developing biomaterials with eco‐friendly properties. Most biopolymers have some limitations because of their poor mechanical properties, high water solubility, or low transparencies. In this study, some biopolymers, that is, silk fibroin (SF) and rice starch (RS) were used as starting materials together with polyvinyl alcohol (PVA) as a film‐former for preparing novel eco‐friendly films. The film preparations were done by solution casting with two different sequences of blending and the film compositions were optimized. Results from UV, SEM, and film properties testing on mechanical properties, degree of swelling, water solubility, and also oxygen permeability indicated that all film properties depended on their compositions and order of blending. The PVA/RS film obtained is transparent with good mechanical properties and low water solubility. The addition of SF increases the permeability of oxygen and also the degradability of the films. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

微波合成含氮掺杂碳量子点改性水性聚氨酯的制备与性能

以柠檬酸和尿素分别为碳源和氮源，微波法合成含氮掺杂碳点N-CDs。以异氟尔酮二异氰酸酯（IPDI）、聚氧化丙烯（PPG-2000）为主要原料，加入不同量的N-CDs制备一系列碳点水性聚氨酯复合材料 （N-CDs/WPU）。通过FTIR、TEM、XPS、UV-vis、荧光光谱和力学性能测试等对复合材料结构和性能进行表征。测试结果表明N-CDs主要由碳氮氧元素组成，表面具有胺基、羟基等活性基团，N-CDs的加入，提高了复合胶膜的力学性能，赋予了胶膜荧光性能。当N-CDs质量分数为0.6%时胶膜拉伸强度达到最大35.00MPa，加入量质量分数为0.8%时荧光强度最佳。     

Effects of plasticizer/cross-linker on the mechanical and thermal properties of starch/PVA blends

Biodegradable blends of potato starch and polyvinyl alcohol were prepared by solution casting method. Citric acid was employed to introduce the plasticizing effect into the starch materials. Glutaraldehyde as cross-linker was used to enhance the properties of the blend films. Cross-linking is a common method to improve the strength and stability of starch products. The effects of citric acid and glutaraldehyde on the mechanical properties, thermal properties and swelling degree were investigated. The prepared films were measured for their antibacterial activities and biodegradability. The blend samples were characterized by the thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and FTIR analysis techniques. From the mechanical properties study, it was analyzed that the blend films showed improvement in their tensile strength after cross-linking with glutaraldehyde. The SEM micrographs indicated that the blend films were smooth without any cracks, pores and were well cross-linked. The TGA curves showed that there was an increase in the thermal stability of the blend films after cross-linking as compared to uncross-linked blend films. The prepared films showed good antibacterial properties against Gam-positive and Gram-negative bacteria. The biodegradability of the blends was determined by placing the samples in compost soil for different time intervals and were found to be biodegradable in nature.     

Synthesis of Alkyl Monoglucoside Citric Monoester and Properties of Its Sodium Salt

A series of disodium alkyl monoglucoside citric monoesters (AG‐EC) were synthesized with an indirect method using glucosides, lauryl/decyl/octyl alcohol and citric acid. The structure and composition of the synthesized surfactants were defined by Fourier transform infrared spectroscopy (FTIR) and liquid chromatography–mass spectrometry (LC/MS). The surface properties, foaming ability and wetting ability were investigated. AG‐EC surfactants exhibited excellent water solubility which eliminated the defect of long‐chain alkyl glucoside. All three surfactants showed high surface activities. AG12‐EC and AG10‐EC showed remarkable foaming abilities in distilled water and hard water. Aqueous solutions of AG‐EC surfactants spread slowly on a parafilm surface.     

Transport properties of cross-linked fullerenol–PVA membranes

Polyhydroxy fullerenes such as fullerenol C₆₀(OH)_22–24 have helped to bridge the gap between fullerenes and their innate solubility issues, where fullerenol solubility in water is 50 mg/ml whereas C₆₀ solubility is 1.3 × 10⁻¹¹ mg/ml. The improved solubility of these fullerene derivatives allows them to be better integrated into composite materials. Here we investigated the transport properties of cross-linked fullerenol–polyvinyl alcohol membranes with the addition of maleic acid for increased stability. High humidity causes the mechanical properties of polyvinyl alcohol to decrease. Using fullerenol as a cross-linker, we were able to decrease the sorption of water with these PVA membranes.     

静电纺PLA/丝素-明胶复合纤维膜的性能研究

通过静电纺丝先制备聚乳酸(PLA)纤维膜,在PLA纤维膜上分别喷射不同比例的丝素-明胶纺丝液制得PLA/丝素-明胶复合纤维膜,对复合纤维膜的溶解性能、尺寸稳定性、力学性能及生物性能进行表征。结果表明:与丝素-明胶纤维膜相比,PLA/丝素-明胶复合纤维膜的溶失率明显下降,尺寸稳定性及柔软性得到改善,且经甲醇处理后,复合纤维膜的力学性能提高。将制备的复合纤维膜进行小鼠胚胎细胞(3T3)培养实验,3T3在PLA/丝素-明胶复合纤维膜上能更好地粘附、伸展和繁殖。     

Synthesis of novel sulfonated polybenzimidazole and preparation of cross-linked membranes for fuel cell application

A novel sulfonated polybenzimidazole, sulfonated poly[2,2′-(p-oxydiphenylene)-5,5′-bibenzimidazole] (SOPBI), was successfully prepared by post-sulfonation reaction of the parent polymer, poly[2,2′-(p-oxydiphenylene)-5,5′-bibenzimidazole] (OPBI), using concentrated and fuming sulfuric acid as the sulfonating reagent at 80 °C, and the degree of sulfonation (DS) could be regulated by controlling the reaction conditions. No significant polymer degradation was observed in the post-sulfonation processes. Direct polymerization of 4,4′-dicarboxydiphenyl ether-2,2′-disulfonic acid disodium salt (DCDPEDS) and 3,3′-diaminobenzidine (DABz), however, resulted in insoluble gels either in polyphosphoric acid (PPA) or in phosphorus pentoxide/methanesulfonic acid (PPMA) in a ratio of 1:10 by weight reaction medium. The SOPBIs prepared by the post-sulfonation method showed good solubility in dimethyl sulfoxide (DMSO), high thermal stability, good film forming ability and excellent mechanical properties. Cross-linked SOPBI membranes were successfully prepared by thermal treatment of phosphoric acid-doped SOPBI membranes at 180 °C in vacuo for 20 h and the resulting cross-linked membranes showed much improved water stability and radical oxidative stability in comparison with the corresponding uncross-linked ones, while the proton conductivity did not change largely. Highly proton conductive (150 mS cm⁻¹, 120 °C in water) and water stable SOPBI membrane was developed.