可降解包装膜的制备及性能研究

用马来酸酐对玉米淀粉进行酯化处理制得醋酸酯淀粉,以溶液共混法分别制备了原淀粉(ST)/聚乙烯醇(PVA)、醋酸酯淀粉(SA)/聚乙烯醇共混膜,用FTIR表征了共混膜的结构;用DSC分析了共混膜的热性能;比较了共混膜的力学性能。结果表明,共混物的加入破坏了PVA的晶态结构,使共混膜的熔融温度向低温方向移动,热稳定性降低,但SA/PVA共混膜的热稳定大大高于ST/PVA共混膜,说明经酯化处理后淀粉的热稳定性增强。并且SA与PVA的相容性也较ST提高,使其共混膜的力学性能改善。表现为SA/PVA共混膜的力学性能明显高于同比例的ST/PVA共混膜。     

聚乙烯醇-羟乙基纤维素共混膜的制备及性能

以羟乙基纤维素(HEC)和聚乙烯醇(PVA)为原料,通过溶液浇铸共混制备不同含量的羟乙基纤维素/聚乙烯醇(HEC/PVA)共混膜,用傅立叶红外分析(FT-IR)、扫描电子显微镜(SEM)进行表征,并考察了HEC/PVA膜的力学性能.结果表明:当PVA质量含量为40％时,共混膜的力学性能较纯HEC有显著提高;温度越低膜的溶胀度越小,但当温度升到60℃以后,膜的溶胀度几乎不变化,说明膜在高温下尺寸的稳定性很好;随着温度的升高,膜的含水率不断增加,制备的共混膜的使用温度不要超过80℃.     

NCC/改性纳米SiO2/PVA共混膜的制备及表征

采用共混法制备了纳米纤维素(NCC)/改性纳米二氧化硅(SiO2)/聚乙烯醇(PVA)共混膜。傅里叶变换红外(FTIR)光谱分析结果表明NCC/改性纳米SiO2/PVA共混膜的共混模式为存在氢键作用力的简单物理共混。力学性能分析结果表明NCC/改性纳米SiO2/PVA共混膜较PVA膜具有较高的拉伸强度,其拉伸强度平均值为128.41 MPa。热学性能分析结果表明NCC/改性纳米SiO2/PVA共混膜较PVA膜具有较好的热稳定性,其最大热失重温度为238℃。扫描电子显微镜(SEM)图分析结果表明NCC/改性纳米SiO2/PVA共混膜样品的表面和断面形貌较规整。     

PSF/PES共混基膜的制备与优化

以聚砜(PSF)、聚醚砜(PES)为膜材料,水为凝胶剂,采用L-S相转化法制备了共混超滤基膜.将均匀设计用于膜制备过程中,用SPSS软件处理实验结果,得到回归方程.描述了PSF/PES含量、PES在共混物中含量、聚乙烯吡咯烷酮含量、丙酮含量对膜透水性能的影响.在优化条件下,膜在0.1 MPa下水通量为290.6 L·m-2·h-1,对500 mg/L的聚乙烯醇(PVA) 88000的截留率高达99.5%.并测得PVA系列对该膜的污染指数FI及膜的化学稳定性,为复合膜提供了理想的支撑膜.     

聚乙烯醇／羧甲基壳聚糖共混膜的结构性能研究

为了提高羧甲基壳聚糖(CMCT)的物理机械性能,采用溶液共混法以羧甲基壳聚糖和聚乙烯醇(PVA)为原料制备不同比例的PVA/CMCT共混膜.用扫描电镜(SEM)观察了共混膜的截面形貌;用DSC、FTIR表征了共混膜的结构;测试了共混膜的力学性能.结果表明:PVA与CMCT分子链间在共混膜中有一定的相互作用,PVA的加入有利于改善CMCT的综合力学性能;当CMCT与PVA质量比为40:60时,两组分相容性好,膜表面均匀光滑规整,共混膜的断裂强度可以达到49 MPa.     

聚乙烯醇聚合度对碱木质素/聚乙烯醇共混膜力学性能的影响

以3种不同聚合度的聚乙烯醇(PVA0588、PVA1788、PVA2488)为原料,添加相同质量分数的碱木质素采用流延法制备共混膜。采用电子万能试验机、扫描电子显微镜、热重分析仪等分析手段对共混膜进行分析表征,并测定了共混膜在不同极性溶剂中力学性能的变化。结果表明:在碱木质素添加量为15%时,碱木质素可较好地分散于PVA相中,3种共混膜的力学性能与各自对应的纯PVA膜相比都有了一定的提高,且当聚合度由PVA0588变化到PVA2488时,共混膜的拉伸强度从35.16MPa增加到48.30MPa,提高了37.37%,断裂伸长率从172.22%增加到247.08%,提高了43.47%;由于PVA聚合度的增大和碱木质素的添加,均使得共混膜的耐溶剂性能和热稳定性增加。     

球状聚乙烯醇-硫脲共混聚合物的制备及对Cu2+的吸附

以聚乙烯醇(PVA)为基体材料,用硫脲和戊二醛的交联产物与PVA共混,将共混物滴入到凝固浴中制备出球状共混树脂.对共混树脂制备过程中的PVA含量、共混配比、凝固浴浓度、Cu2+的吸附率、Cu2+的解吸等因素进行了研究.结果表明,在PVA的质量分数含量为8.0％、PVA与硫脲的质量比为5∶1、凝固浴中磷酸氢二钠和硼酸的质...     

PVA抗氧化膜的制备与性能研究

以聚乙烯醇(PVA)为膜基质,添加天然抗氧化剂槲皮素(Quercetin)功能组分,通过溶液浇铸法制备共混包装膜。研究了不同含量槲皮素、不同含量聚乙烯醇对共混膜的机械性能,抗氧化性能和迁移的影响。结果表明随着槲皮素含量的提高,共混膜的抗氧化性能和氧化剂的迁移显著提高;随着聚乙烯醇含量的提高,共混膜的断裂伸长率和断裂强度显著提高,随着槲皮素含量比例的提高,共混膜的力学性能稍有提高。而且,共混膜可显著提高水果的抗氧化性,可是其货架期延长2 d以上。本研究为环境友好型包装材料的制备及在果蔬包装材料中的应用提供了理论依据。     

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。     

Deduction of a facile method to construct Antheraea mylitta silk fibroin/gelatin blend films for prospective biomedical applications

Blend films of two types (I and II) were prepared by mixing Antheraea mylitta silk fibroin (AMF) and gelatin solution in various blend ratios via the solution casting method. Two different crosslinkers, namely glutaraldehyde and genipin, were used during blend preparation. The structural characteristics and thermal properties of the blend films were examined by Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), Thermogravimetric analysis (TGA) and Diffrential scanning calorimetery (DSC). The FTIR spectra showed conformational alterations in type I blend films while type II films attained high β‐sheet crystallinity. The XRD diffractograms presented a high degree of crystallinity in type II blend films compared to type I, which showed an almost amorphous structure. Further, thermal and biological studies were conducted on type II films. According to the TGA thermograms, the degradation temperature of the crosslinked blend films shifted compared to pure gelatin and pure AMF films. Partial miscibility of the two components was indicated by DSC thermograms of the blends. The high water uptake capacity of type II blend films was found to imitate hydrogel behaviour. The blend films did not show any toxicity in 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide (MTT) assay and supported L929 fibroblast cell spreading and proliferation. The biodegradation of the blend films was significantly faster than the pure silk film. © 2020 Society of Industrial Chemistry     

Thermal,Mechanical and Chemical Properties of Hydrophilic Poly(vinyl alcohol) Film Improved by Hydrophobic Poly(propylene glycol)

A series of poly(vinyl alcohol)/poly(propylene glycol) (PVA/PPG) blend films with different PPG contents were prepared by casting the polymer blend solutions. Structure and morphologies of the PVA/PPG blend films were studied by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PVA/PPG blend films were investigated by differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), tensile strength tests, and other physical methods. It was revealed that the introduction of PPG could exert marked effects on the morphology and the properties of PVA film.     

Preparation and characterization of konjac glucomannan/poly(diallydimethylammonium chloride) blend films

A novel preservative film was prepared by blending konjac glucomannan (KGM) and poly (diallydimethylammonium chloride) (PDADMAC) in aqueous system. The effects of PDADMAC content on the miscibility, morphology, thermal stability, and mechanical properties of the blend films were investigated by density determination, scanning electron microscopy (SEM), attenuated total reflection infrared spectroscopy (ATR‐IR), X‐ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile tests. The results of the density determination predicted that the blends of KGM and PDADMAC were miscible when the PDADMAC content was less than 70 wt %. Moreover, SEM and XRD confirmed the result. ATR‐IR showed that strong intermolecular hydrogen bonds interaction occurred between the negative charge groups of KGM and the quaternary ammonium groups of PDADMAC in the blends. The tensile strength and the break elongation of the blends were improved largely to 106.5 MPa and 32.04%, when the PDADMAC content was 20 wt %. The thermal stability of the blends was higher than pure KGM. Results from the film‐coating preservation experiments with lichi and grapes showed that the blend film had excellent water‐holding and preservative ability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Preparation and Characterization of Gelatin-Based PVA Film: Effect of Gamma Irradiation

Gelatin-based polyvinyl alcohol (PVA) films were prepared (using a casting process) by mixing aqueous solutions of gelatin and PVA in different ratios. Monomer 1, 4-butanediol diacrylate (BDDA) was dissolved in methanol. Films containing 95% gelatin + 5% PVA were soaked in 3% BDDA monomer (w/w). These films were then irradiated under gamma radiation (⁶⁰Co) at different doses (50–500 krad) at a dose rate of 350 krad/h. The physico-mechanical and thermal properties of these films were evaluated. It was evident that 5% PVA-containing gelatin blend film exhibited the highest tensile strength (TS) value at 50 krad (51 MPa), which was 46% higher than that of non-irradiated blend films. It was also found that incorporation of PVA significantly reduced the TS value of the blend films compared to the raw film, whereas elongation at break (Eb) value was increased. A significant improvement of the blend films was also confirmed by thermogravimetric analysis (TGA) and thermo-mechanical analysis (TMA) when the acrylate group (from BDDA) was introduced into the film.     

Preparation and characterization of poly(vinyl alcohol) and gelatin blend films

Poly(vinyl alcohol) (PVA) is a water-soluble polymer that has been studied intensively because of several interesting physical properties that are useful in technical applications, including biochemical and medical applications. In this article, we report the effects of the addition of gelatin on the optical, microstructural, thermal, and electrical properties of PVA. Pure and PVA/gelatin blend films were prepared with the solution-casting method. These films were further investigated with Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), ultraviolet–visible (UV–vis) spectroscopy, and dielectric measurements. The FTIR spectrum shows a strong chemical interaction between PVA and gelatin molecules with the formation of new peaks. These peaks are due to the presence of gelatin in the blend films. The DSC results indicate that the addition of gelatin to PVA changes the thermal behavior, such as the melting temperature of PVA, and this shows that the blends are compatible with each other. This also shows that the interaction of gelatin and PVA molecules changes the crystallite parameters and the degree of crystallinity, and this supports the XRD results. The UV–vis optical study also reflects the formation of the complex and its effect on the microstructure of the blend film. Moreover, the addition of gelatin also gives rise to changes in the electrical properties of PVA/gelatin blend films. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Studies of chitosan. I. Preparation and characterization of chitosan/poly(vinyl alcohol) blend films

Various blending ratios of chitosan/poly (vinyl alcohol) (CS/PVA) blend films were prepared by solution blend method in this study. The thermal properties and chemical structure characterization of the CS/PVA blend films were examined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), and Fourier transform infrared (FTIR). Based upon the observation on the DSC thermal analysis, the melting point of PVA is decreased when the amount of CS in the blend film is increased. The FTIR absorption characteristic is changed when the amount of CS in the blend film is varied. Results of X‐ray diffraction (XRD) analysis indicate that the intensity of diffraction peak at 19° of PVA becomes lower and broader with increasing the amount of CS in the CS/PVA blend film. This trend illustrates that the existence of CS decreases the crystallinity of PVA. Although both PVA and CS are hydrophilic biodegradable polymers, the results of water contact angle measurement are still shown as high as 68° and 83° for PVA and for CS films, respectively. A minimum water contact angle (56°) was observed when the blend film contains 50 wt % CS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

葡甘聚糖-壳聚糖-聚乙烯醇共混膜的结构表征及性能研究

用溶液共混法制备了葡甘聚糖-壳聚糖-聚乙烯醇共混膜,并用红外光谱(FTIR)、X-射线衍射(XRD)、扫描电镜(SEM)及透光率表征了膜的结构,同时测定了共混膜的力学性能、吸水率、水蒸气透过率。结果表明:共混膜中葡甘聚糖、壳聚糖及聚乙烯醇之间存在着强烈的相互作用和良好的相容性,三者共混明显改善了纯聚合物和二元膜的性能。     

Physicochemical and morphological evaluation of chitosan/poly(vinyl alcohol)/methylcellulose chemically cross-linked ternary blends

Chitosan/poly(vinyl alcohol)/methylcellulose (CS/PVA/MC) ternary blend was prepared and chemically cross-linked with glutaraldehyde. The prepared ternary blends were characterized by Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The FTIR results showed that the strong intermolecular hydrogen bonds took place between CS and PVA. TGA showed the thermostability of the blend is enhanced by glutaraldehyde as crosslink agent. Results of XRD indicated that the relative crystalline of pure CS film was reduced when the polymeric network was reticulated by glutaraldehyde. Finally, the results of scanning electron microscopy (SEM) indicated that the morphology of the blend is rough and heterogenous, further it confirms the interaction between the functional groups of the blend components.     

Characterization of polyvinyl alcohol/gelatin blend hydrogel films for biomedical applications

In the present investigation, attempt was made to prepare blend hydrogel by esterification of polyvinyl alcohol with gelatin. The blend hydrogel was further converted into films by the conventional solution‐casting method. These films were characterized by FTIR, DSC, and X‐ray diffraction studies. The refractive index and viscosity of different composition of the blends were measured in the solution phase of the material. The mechanical properties of the blend films were measured by tensile test. Swelling behavior of the blend hydrogel was also studied. The FTIR spectrum of the blend film indicated complete esterification of the free carboxylic group of gelatin. The DSC results indicate that the addition of gelatin with PVA changes the thermal behavior like melting temperature of PVA, which may be due to the miscibility of PVA with gelatin. The interaction of gelatin with PVA molecule changes the crystallite parameters and the degree of crystallinity. The crystallinity of the blend film was mainly due to gelatin. The comparison of viscosity indicated an increase in the segment density within the molecular coil. The results revealed the changes observed in the properties of the gel, and it enhances the gel formation at viscoelastic phase of the material. The blend film had sufficient strength and water‐holding capacity. The results obtained indicated that the blend film could be used for various biomedical applications such as wound dressing and drug‐delivery systems. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Effect of glycerin on structure transition of PVA/SF blends

Blend films of silk fibrion (SF) and poly(vinyl alcohol) (PVA), with glycerin as an additive, were made, and the structure and properties of the blends were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FT‐IR) spectroscopy, differential scanning calorimetry (DSC), and wide‐angle X‐ray diffraction (WAXD) and with an Instron Material Tester. The results showed that SF and PVA are principally incompatible and the blends made by the two polymers were phase‐separated. The results, however, also demonstrated that the blend structure could be changed to some extent by addition of 3–8% glycerin. The boundary of the PVA and SF phases became indistinct, as reported by SEM, a new peak appeared in the WAXD curves, the width of the OH absorption peak in the FT‐IR spectra increased, and the melting points changed in the DSC curves. In particular, the mechanical properties obviously increased, from 350 kg/cm² and 10% of PVA/SF (80/20) film to 832 kg/cm² and 39% of PVA/SF (80/20) film because of the increase in glycerin. It was suggested that glycerin plays a role in building the relationship between PVA and SF, strengthening the interaction between them and improving their compatibility. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2342–2347, 2002