改性淀粉/PVA水溶性薄膜的制备与性能表征

研究了PVA含量对薄膜力学性能的影响,改性淀粉的含量对薄膜水溶性的影响。结果表明,所制得的薄膜的性能优异,其拉伸强度为20 MPa,水溶时间为136 s。采用的制备方法工艺简单、成本低、能耗低、效率高、具有较高的实际应用价值。     

接枝率对CS-g-PAA粘合与薄膜性能的影响

通过先对玉米淀粉进行季铵型阳离子化预处理,再采用Fe2+-H2O2氧化还原体系,引发阳离子淀粉与丙烯酸(AA)进行接枝共聚反应,制备了一系列具有不同接枝率的阳离子淀粉接枝聚丙烯酸(CS-g-PAA),研究了接枝率对CS-g-PAA薄膜性能及其与纤维之间粘合强度的影响。结果表明,这种接枝共聚合能够提高阳离子淀粉的粘合强度及薄膜性能;随着接枝率的提高,CS-g-PAA的粘合强度增大,薄膜的断裂强度降低,断裂伸长率增加,水溶性提高,吸湿率增大。综合考虑接枝效率、粘合强度和薄膜性能,CS-g-PAA的接枝率为8.5%为宜。     

接枝率对CS-g-PAA粘合与薄膜性能的影响

通过先对玉米淀粉进行季铵型阳离子化预处理,再采用Fe2+-H2O2氧化还原体系,引发阳离子淀粉与丙烯酸(AA)进行接枝共聚反应,制备了一系列具有不同接枝率的阳离子淀粉接枝聚丙烯酸(CS-g-PAA),研究了接枝率对CS-g-PAA薄膜性能及其与纤维之间粘合强度的影响。结果表明,这种接枝共聚合能够提高阳离子淀粉的粘合强度及薄膜性能;随着接枝率的提高,CS-g-PAA的粘合强度增大,薄膜的断裂强度降低,断裂伸长率增加,水溶性提高,吸湿率增大。综合考虑接枝效率、粘合强度和薄膜性能,CS-g-PAA的接枝率为8.5%为宜。     

APAM/淀粉共混薄膜力学性能及粘合强度的研究

以丙烯酰胺(AM)、丙烯酸(AA)和丙烯酰氧乙基三甲基氯化铵(DAC)为共聚合单体,通过水溶液聚合合成两性聚丙烯酰胺(APAM),然后探索了它与淀粉的共混比对纤维粘合强度的影响,研究了这种共混物的薄膜性能。研究结果表明,APAM与淀粉共混后能够明显改善对棉和涤纶纤维的粘合强度,随着APAM用量的增加,对棉和涤纶纤维粘合强度逐渐增大;通过与APAM的共混,能够降低淀粉膜的脆性,对淀粉膜具有增韧作用;并能缩短淀粉膜的水溶时间、增加吸湿率和水溶胀率,有利于纺织退浆。     

PVA吹塑薄膜生产工艺

介绍了PVA(聚乙烯醇)薄膜的工艺特性和吹塑法生产PVA薄膜的工艺流程。     

乙酰淀粉/PVA共混体系转矩流变试验研究

为开发性能良好的可塑性淀粉塑料,将转矩流变设备、正交分析方法和DPS统计处理相结合并首次引入淀粉研究领域。首先用转矩流变仪模拟了乙酰淀粉/聚乙烯醇(PVA)共混体系的挤出加工过程,并以L16(45)正交试验结合DPS统计处理系统综合考察了PVA比例、增塑剂、转速、温度对共混体系转矩流变性的影响。结果表明:共混体系在170℃、转速15 r/m in条件下每100g乙酰淀粉加入20g甘油、5g山梨醇和10g PVA时可以得到较好的转矩流变性能,同时还验证和讨论了实验影响因子的交互影响效应。     

淀粉/PVA生物降解材料的热塑性研究

将聚乙烯醇(PVA)、淀粉、增塑剂在Hakke流变仪中共混制备了热塑性淀粉/PvA材料,研究了2种PVA-PVA1799、PVA1788,2种淀粉-玉米淀粉、木薯淀粉的热塑性情况;比较了甘油、乙二醇、乙酰胺3种增塑剂的增塑效果.结果表明:采用合适的增塑剂与适当的PVA、淀粉组合可以使PVA/淀粉共混体系在高温下热塑成型...     

PVA/淀粉薄膜挤出吹塑工艺及性能研究

采用挤出造粒和吹塑工艺连续制备了聚乙烯醇/淀粉薄膜.探讨了淀粉含量、增塑剂含量、增塑剂中水含量和混料条件对PVA/淀粉薄膜加工温度、熔体流动性和薄膜力学性能的影响.结果表明,随着淀粉含量的增加,增塑剂含量的增加,物料的加工温度降低;随着增塑剂中水含量的增加,挤出造粒温度升高,吹膜温度不变;PVA/淀粉共混物优选的造粒温度是165～180℃.吹膜温度是205～220℃;淀粉含量为35%～50%,增塑荆含量60份以上,增塑剂中的水含量为1/6～1/3时,共混物有较好的加工流动性;分批逐滴加入增塑剂并在80～110℃下混料,可以使PVA/淀粉充分溶胀.利于热塑性加工;淀粉含量为40%、增塑剂含量为60份、增塑剂中的水含量为33%时,薄膜力学性能最佳.     

可生物降解PVA/淀粉/环氧化天然橡胶三元共混体的表面改性和溶胀性能

采用可生物降解的聚合物是解决废弃橡胶制品的方法之一。研究人员将PVA、淀粉和环氧化天然橡胶共混制成可生物降解的聚合物。聚合物共混体薄膜在水中的溶胀比、拉伸强度可用扫描电子显微镜测定。研究人员发现10%的ENR、80%的淀粉和20%的PVA共混的聚合物,其综合性能可达到最佳水平。     

季铵阳离子淀粉/PVA共混膜的性能研究

将季铵阳离子淀粉(QS)与聚乙烯醇(PVA)分别煮浆,之后按所需比例进行混合来制备共混膜,利用红外光谱仪(FTIR)、X射线衍射仪(XRD)、扫描电镜(SEM)对共混膜进行表征并测试了其力学性能。结果表明,QS变性程度、PVA聚合度与醇解度、共混比对共混膜的性能都存在很大关系。增加QS取代度,共混膜的断裂强度与断裂伸长率提高、磨耗降低;增大PVA的聚合度与醇解度,有助于提高共混膜断裂强度和断裂伸长率;随着QS含量的增多,共混膜的断裂强度增大,断裂伸长率减小。     

季铵阳离子淀粉/PVA共混膜的性能研究

将季铵阳离子淀粉(QS)与聚乙烯醇(PVA)分别煮浆,之后按所需比例进行混合来制备共混膜,利用红外光谱仪(FTIR)、X射线衍射仪(XRD)、扫描电镜(SEM)对共混膜进行表征并测试了其力学性能。结果表明,QS变性程度、PVA聚合度与醇解度、共混比对共混膜的性能都存在很大关系。增加QS取代度,共混膜的断裂强度与断裂伸长率提高、磨耗降低;增大PVA的聚合度与醇解度,有助于提高共混膜断裂强度和断裂伸长率;随着QS含量的增多,共混膜的断裂强度增大,断裂伸长率减小。     

木质素/PVA复合膜的性能

以可再生资源木质素磺酸钙和聚乙烯醇(PVA)为基料,制备力学强度及耐水性能良好的木质素/PVA复合膜。采用5因素二次正交旋转组合设计研究了木质素磺酸钙、PVA、甲醛、尿素、硼砂对膜拉伸强度、断裂伸长率和吸水率的影响,并得到相应二次回归模型。分析表明:5个因素的一次项、二次项及交互项对膜拉伸强度、断裂伸长率和吸水率均有不同程度的影响。当原料配比为木质素磺酸钙7 g、PVA 14 g、甲醛10 g、尿素7 g、硼砂2.5 g时,可以得到拉伸性能和耐水性优良的木质素/PVA复合膜。     

Effects of additives with different functional groups on the physical properties of starch/PVA blend film

The effects of additives with different functional groups, that is, hydroxyl and carboxyl groups, on the physical properties of starch/PVA blend films were examined. Starch/PVA blend films were prepared by the mixing process. Glycerol (GL) with 3 hydroxyl groups, succinic acid (SA) with 2 carboxyl groups, malic acid (MA) with 1 hydroxyl and 2 carboxyl groups, and tartaric acid (TA) with 2 hydroxyl and 2 carboxyl groups were used as additives. The results of measured tensile strength and elongation verified that hydroxyl and carboxyl groups as functional groups increased the flexibility and strength of the film. The degree of swelling (DS) and solubility (S) of the GL/SA‐added films were low. However, the DS and S of the films with added MA or TA with both hydroxyl and carboxyl groups were comparatively high. When the film was dried at low temperature, the properties of the films evidently improved, probably because hydrogen bonding was activated at low temperature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3733–3740, 2006     

水转印用PVA水解膜的研究

以聚乙烯醇1788(PVA)作为原料,以甘油(丙三醇)作为增塑剂,采用流延法制作水转印膜,研究水解膜溶解时间、平衡含水率及制膜溶液粘度的影响因素。实验发现,聚乙烯醇薄膜的溶解时间会随着溶解水温、甘油比例的增加而减少,随着膜厚的增加而增加;薄膜的平衡含水率随着环境湿度及甘油比例的增加而增加,且平衡含水率在甘油质量分数小于6%时增加平缓,大于6%时增加比较迅速;在聚乙烯醇水溶液中添加一定的甘油后,随着甘油比例的增加,聚乙烯醇水溶液的粘度会相对减小;在低剪切速率下,质量分数为15%聚乙烯醇水溶液粘度会随着剪切速率的增加而增加。     

Physical properties of PVA/PSSNa blends

Blends of conductive polymers with conventional nonconductive ones have, together, the virtues of good electroconductivity and good mechanical properties, whose prospect for electronic industrial application is very good. We prepared poly(vinyl alcohol) (PVA)–sodium polystyrene–sulfonate (PSSNa) blends through aqueous solution casting; the films are flexible and transparent, with electroconductivity that could reach 10^?5 S/cm. The dependence of the electroconductivity on the weight fraction of PSSNa was found to follow the percolation theory. A general discussion is given on the factors that could influence the percolation threshold and the exponent. The films are stable in a 30% KOH solution and keep their conductivity after 10 days' exposure. Some mechanical properties are measured and the best mixing ratio is obtained for future use. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 79–87, 2003     

Dichroic and spectral properties of anthraquinone-based azo dyes for PVA polarizing film

Dichroic dyes with broad absorption bands are advantageous for the production of neutral gray polarizing films. For this purpose, anthraquinone-based azo dyes were synthesized to have a conjugated bichromophore design and this was applied to PVA polarizing films. The spectral and dichroic properties of the polarizing films were examined and compared to the films produced with a general disazo dichroic dye. The polarizing films with anthraquinone-based azo dyes had wider absorption bands, but lower dichroic ratios compared to the films with a general disazo dichroic dye. It was found that the alignment between the transition moments of the anthraquinone and azo chromophores is an important factor for the dichroic properties of anthraquinone-based azo dyes.     

改性聚乙烯醇/淀粉无醛胶粘剂的研究

介绍了一种不含甲醛、环保的聚乙烯醇/淀粉胶粘剂的合成方法,探讨了改性机理,并对聚乙烯醇淀粉的配比、次氯酸钠用量、过硫酸钾用量等影响胶粘剂性能的因素进行了讨论。该胶粘剂可代替酚醛胶粘剂作为木材、胶合板用胶粘剂。     

快干型淀粉／聚乙烯醇胶粘剂研究

实验对利用聚乙烯醇、玉米淀粉、高岭土,制造的环保快干型水性高分子胶粘剂的配方进行了系统的研究,通过考察原料配比、氧化剂、交联剂等影响确定出胶粘剂的最终配方。     

PVA/ P（AA-Co-AN）/ PVA渗透汽化膜的研究

制备一种PVA/P(AA-Co-AN)/PVA复合膜用于甲醇水溶液的分离,膜的主体部分P(AA-Co-AN)由添加纳米S iO2粉末的丙烯酸(AA)和丙烯腈(AN)通过溶液共聚制得,两侧为交联聚乙烯醇(PVA)。考察了复合膜在高质量分数甲醇水溶液中的溶胀性能,探讨了浸泡液温度及浸泡液质量分数对溶胀度的影响,测试了复合膜的力学性能。考察了不同单体配比〔n(AA)∶n(AN)〕所制备的复合膜在不同质量分数甲醇水溶液,不同温度下的渗透汽化性能。结果显示,复合膜在高质量分数甲醇水溶液中具有良好的溶胀性能及渗透汽化性能;在n(AA)∶n(AN)=1∶1下所制备的复合膜,对高质量分数甲醇水溶液分离效果最佳,60℃时分离w(甲醇)=98%的水溶液,分离因子可达1 534,通量为583 g/(m2.h)。