交联壳聚糖/蒙脱土复合膜的制备及性能研究

以壳聚糖（CS）为基质材料，蒙脱土（MMT）为填料，采用戊二醛（GA）交联改性并结合溶液插层法制备了交联壳聚糖/蒙脱土（CS/GA/MMT）复合膜。通过扫描电子显微镜、X射线衍射仪、红外光谱仪及热重分析仪对复合膜的结构进行了表征，考察了MMT用量对复合膜的吸水性能、水蒸气阻隔性能和力学性能的影响。结果表明，交联改性CS可提高CS膜的耐水性，CS/GA膜的吸水率较CS膜降低了9.6 %；MMT可提高复合膜的耐水性、水蒸气阻隔性能、力学性能和热稳定性；当MMT的用量为CS质量的5 %时，复合膜的各项性能较好，吸水率、水蒸气透过率和断裂伸长率较CS膜分别降低了37.3 %、36.7 %和41.9 %，且拉伸强度提高了160.5 %。     

交联壳聚糖/聚乙烯醇/蜗牛黏液复合膜的制备及性能研究

采用延流法制备了香兰素（V）交联的壳聚糖/聚乙烯醇/蜗牛黏液（CS/PVA/SM）复合膜,并通过热重分析仪（TG）、扫描电子显微镜（SEM）和万能材料试验机等研究了不同CS/SM配比对复合膜光学性能、水蒸气和氧气阻隔能力、力学性能、热力学性能及生物降解性能等的影响。结果表明,CS/PVA/SM复合膜为可降解的亲水性薄膜,当CS溶液/SM溶液体积比为5/3时,复合膜性能优良,其抗氧化活性为87.51 %,其水蒸气透过率比纯CS膜降低了75.16 %,不透明度降低了87.74 %,拉伸强度提高了16.04 %,断裂伸长率提高了28.26倍;随着SM含量的增加,复合膜的热稳定性有所降低;CS溶液/SM溶液体积比为5/1、5/2和5/3时,复合膜表现出良好的相容性;SM的添加使复合膜具有很好的延展性和柔韧性,V的添加提高了复合膜的拉伸强度和抗氧化能力;所制备的CS/PVA/SM复合膜在食品包装领域中有潜在的应用前景。     

鱼鳞明胶/壳聚糖/薰衣草精油抗菌复合膜制备及性能

以鱼鳞明胶(SG)和壳聚糖(CS)为原料,薰衣草精油(LEO)为抗菌剂,通过共混法制备抗菌复合膜,通过FTIR、XRD、SEM和热重分析对复合膜的形貌和结构进行表征及对力学、光学、阻隔、抑菌等性能测试分析。结果表明,LEO与SG/CS基膜较好复合,与SG/CS基膜相比,当LEO添加量为1%时,复合膜具有良好的力学强度(26.36 MPa),断裂伸长率提升了12.96%；透明度有所下降,透光率为70.50%；耐水性能和水蒸气阻隔性能显著增强,含水率、水溶性和水蒸汽透过率分别下降了22.48%、30.49%和26.03%；DPPH自由基清除率提高了247.88%,抗氧化性显著提高；同时对大肠杆菌和金黄色葡萄球菌具有良好的抑菌作用。     

抗菌聚乙烯薄膜的制备及性能研究

以聚乙烯(PE)为基材,添加脱氢乙酸钠、苯甲酸钠、金属钠离子改性剂、脱氢乙酸钠/苯甲酸钠等抗菌剂,通过双螺杆挤出装置造粒及流延机流延制备成改性抗菌PE薄膜,并研究抗菌剂的加入对薄膜的力学性能、光学性能、水蒸气透过量、氧气透过量及抑菌效果的影响。结果表明,与纯的低密度聚乙烯薄膜相比,分别添加0.8%的脱氢乙酸钠、0.8%苯甲酸钠、0.48%脱氢乙酸钠/0.32%苯甲酸钠、0.8%金属钠离子改性剂的四种抗菌薄膜的断裂伸长率减小,雾度增大,透光率下降,氧气透过量降低;添加0.8%金属钠离子改性剂和0.48%脱氢乙酸钠/0.32%苯甲酸钠的抗菌薄膜的拉伸强度减小,其他两种抗菌薄膜拉伸强度增大,0.8%金属钠离子改性剂改性薄膜的水蒸气透过量增大,其他改性薄膜的水蒸气透过量均减小;所有改性薄膜对大肠杆菌和金黄色葡萄球菌均有抑制效果。改性抗菌薄膜可以作为新型包装材料,应用于食品活性包装中。     

聚乙烯醇 /改性氧化石墨烯阻隔涂层的制备及性能研究

为研制高阻隔性能的聚乙烯醇涂层,选用氨基磺酸盐化合物对氧化石墨烯（GO）进行化学改性制备改性氧化石墨烯（SGO）,与聚乙烯醇（PVA）溶液共混制备了聚乙烯醇 /改性氧化石墨烯纳米复合膜及纳米复合涂层（PET基材）。探究了 SGO的结构变化及对复合膜力学性能的影响,以及不同含量的 SGO（20%~80%）对 PVA/SGO复合涂层阻水阻氧性能的影响。结果表明：氨基磺酸盐化合物成功改性并插入 GO层间; SGO的加入增强了复合膜的拉伸强度;复合涂层具有良好的有序排列结构,这种结构降低了 PET的水蒸气透过率和氧气透过量,当 SGO含量为 80%时, PET的水蒸气透过率和氧气透过量都达到最低,为 6. 99 g/（m²·d）和 0. 33 cm³（/ m²·24 h·0. 1 MPa）,同时在高湿度下复合涂层也保持较低的氧气透过量。     

纳米纤维/氧化淀粉/PVA复合膜制备及特性

以甘蔗渣为原料,采用硫酸水解法制备甘蔗渣纳米纤维素。以氧化淀粉(OS)和聚乙烯醇(PVA)为基材,添加甘蔗渣纳米纤维素、增塑剂甘油、交联剂乙二醛制备复合膜。以拉伸强度、断裂伸长率、水蒸气透过率和水溶率为测量指标,研究了甘油、乙二醛、纳米纤维添加量对膜特性的影响。结果表明,随着甘油含量增大,复合膜的水溶率和水蒸气透过率逐渐增大,拉伸强度逐渐降低;添加乙二醛能够提高复合膜的耐水性能,添加量为0. 15 m L/g时,拉伸强度达到最大值(6. 25±0. 16) MPa;适当添加甘蔗渣纳米纤维素增强复合膜的机械性能和耐水性能,当纳米纤维含量为20%时,复合膜的水蒸气透过率达到最小值,为(5. 349±0. 056)×10~(-7)g/(m·h·Pa)。     

蛭石/PBAT复合薄膜的制备与性能

使用蛭石（VMT）作为填料,以可生物降解的聚对苯二甲酸-己二酸丁二醇酯（PBAT）作为基体,采用熔融-吹塑法制备出蛭石/聚对苯二甲酸-己二酸丁二醇酯（VMT/PBAT）复合薄膜,并通过添加聚苯乙烯马来酸酐共聚物（SMA）作为相容剂制备了VMT/PBAT/SMA复合薄膜。对纯PBAT薄膜、VMT/PBAT和VMT/PBAT/SMA复合薄膜的热性能、流变性能、水蒸汽阻隔性能、断面微观结构和力学性能进行了测试。结果表明,相比纯PBAT薄膜,蛭石的填充使VMT/PBAT复合薄膜的热稳定性降低,相容剂SMA的添加增强了VMT/PBAT/SMA复合薄膜的热稳定性;蛭石的添加使复合薄膜的结晶度降低了约2%。水蒸汽透过量测试表明,两种复合薄膜水蒸汽阻隔性能符合国家标准;VMT的添加使VMT/PBAT复合薄膜的拉伸强度和断裂伸长率降低,而添加相容剂SMA使VMT/PBAT/SMA复合薄膜的拉伸强度和断裂伸长率相比VMT/PBAT复合薄膜提高约10 %。     

空气除湿用抗菌透湿复合膜的制备

为提高膜式全热交换器的除湿性能并使膜具备抗菌性能,以Li Cl为亲水添加剂,Ag NO3为抗菌剂,添加到聚乙烯醇（PVA）水溶液中制成铸膜液,以聚丙烯（PP）膜为支撑层,制备了一种抗菌透湿复合膜。搭建了薄膜透湿性测量平台,测试了复合膜的水蒸气透过量,对复合膜的抗菌性进行了检测。结果表明,复合膜的水蒸气透过量随Li Cl含量的增加而增加,Li Cl含量为5%的复合膜是不含Li Cl复合膜的1.79倍,是商用纸膜的2.67倍。加入Ag NO3后薄膜的透湿性没有明显变化,抗菌实验结果显示,复合膜对表皮葡萄球菌、大肠杆菌有抗菌作用,对表皮葡萄球菌的抗菌作用更强。     

增塑剂TEC对PLA/PHB复合膜性能的影响

采用挤出吹塑法制备PLA/PHB复合膜,并利用液体增塑剂柠檬酸三乙酯(TEC)对PLA/PHB复合膜进行增塑改性。对不同TEC比例改性后的复合膜进行力学性能、透氧透湿、DSC性能测试,并结合红外光谱扫描、SEM断面观察,分析TEC添加前后复合材料的微观结构形态变化。结果表明:当TEC含量为7.5%时,复合薄膜具有较优的力学性能、透湿性能以及透气性能。DSC分析、IR分析以及SEM分析表明,TEC对复合材料的增塑作用比较明显,能够显著提高PLA/PHB复合膜玻璃化转变温度,提高复合膜的热稳定性能,改进断裂伸长率,提高材料的柔软性。     

纳米SiO_2/壳聚糖/淀粉复合包装膜的制备及性能

选用壳聚糖(CH)和木薯(CA)淀粉为基本成膜材料,甘油为增塑剂,改性纳米SiO_2(NS)为增强剂,采用流延法制备壳聚糖-淀粉基复合膜,探究壳聚糖与木薯淀粉比例、甘油含量以及改性纳米SiO_2含量对复合膜性能的影响。通过正交试验采用极差分析并结合方差分析确定了纳米SiO_2/壳聚糖/淀粉复合膜的较优工艺条件。结果表明,壳聚糖与淀粉质量比6∶4,甘油含量35%,改性纳米SiO_2含量2%。在此条件下,复合膜的各项性能分别为:拉伸强度32.43 MPa,断裂伸长率38.98%,透光度19.96,水蒸气透过率10.53×10~(-11)/(m·s·Pa)。该复合膜与不添加改性纳米SiO_2的复合膜相比其力学强度增加了158.41%,水蒸气透过率减小了13.48%,复合膜力学强度和耐水性能有明显的改善。     

海泡石增强壳聚糖/玉米醇溶蛋白复合膜的制备及性能

采用流延成膜法制备了不同海泡石(SP)质量分数的壳聚糖(CS)/玉米蛋白(ZN)复合膜。研究了SP质量分数对CS/ZN复合膜机械性能和断面形貌的影响,分析了SP对CS/ZN复合膜的增强机理。扫描电子显微镜结果表明,SP粒子在复合膜中分散较好,CS与ZN之间有较好的相容性。随着SP质量分数增加,SP/CS/ZN膜拉伸强度先增加后减小,当SP质量分数为2%时,其拉伸强度达到最大值21.1 MPa,比纯CS/ZN提高了8.1%;而断裂伸长率随着SP质量分数先增加后降低,从15.3%下降为7.5%;同时复合膜的耐水性能上升,复合膜的吸水率随着SP质量分数增加先减小后增加,在8%时达到最小值。SP的引入导致复合膜的透光性能下降,SP质量分数为6%时在波长800 nm处光透过率下降约20%。     

醋酸纤维素/壳聚糖复合膜制备与性能优化

为拓展醋酸纤维素(CA)在可降解包装材料中的应用,采用溶液共混法制备了醋酸纤维素(CA)和壳聚糖(CS)复合膜,研究了CS含量对CA/CS二元复合膜性能的影响。通过观察并分析复合膜的形貌、断面结构、化学键发现,CS能够充分结合膜内外的孔隙结构,两者之间强烈的相互作用增强了复合膜的各项性能。性能测试结果表明,当CS含量为10%时,复合膜的力学性能达到最大,断裂伸长率及抗拉强度分别增加12.37%和38.62 MPa,降解损失率提高了50.14%。同时,抑制了大肠杆菌及金黄色葡萄球菌的生长,抗菌率最高能够达到73.9%和54.6%。因此,CS在提高CA膜的力学性能和降解性能的同时,还赋予了复合膜优异的抗菌性。     

Influence of forming method of blending versus casting layer-by-layer on structural properties and packing performances of casein-gelatin composite edible film under different appending proportion

In order to obtain casein edible films with great packing performance, gelatin as the reinforcing additive with different ratios were loaded via two methods including layer- by- layer and blending. A comparative study on structure properties between double layers and blending films made from casein and gelatin was obtained by scanning electron microscopy and Fourier transform infrared spectroscopy. The difference between the films' packing characters were conducted by water vapor permeability (WVP), optical property, and mechanical properties (including tensile strength (TS) and elongation (EAB)). The results showed that the degree of films roughness increased and the structural stability decreased as the increase of gelatin additive ratio in both double layers and blending films. Thickness and WVP both displayed a trend of increasing first then decreasing at the dividing of gelatin instead of casein in 50%. Importantly, WVP values in double layers film with a largest value of 6.95 gm⁻¹Pa⁻¹s⁻¹ was higher than blending films, observably (P < 0.05). Additionally, TS in blending film was increased by 23.44% than double layers film under the gelatin additive proportion of 70%, and EAB value in double layers film was larger by 207.65% than blending film under the gelatin additive proportion of 10%.     

Influence of preparation conditions on the physical properties of zein films

Zein is a hydrophobic protein produced from maize. Biodegradable zein films without additional reagents were prepared using various controlled drying conditions. The zein films were transparent. Mechanical properties (tensile strength and puncture strength), gas permeability, and water vapor permeability (WVP) of the zein films were measured. The tensile strengths of the zein films were between 7 and 30 MPa and the puncture strengths between 37 and 191 MPa. The zein films had higher oxygen permeability than carbon dioxide permeability. The lowest WVP of the zein film was 0.012×10⁻⁹ g·m/m²·s·Pa. We found differences in the WVP between the sides of the zein films; i.e., the air side of the zein film had a higher WVP than the basal side of the zein film when the films were exposed to high humidity during testing. This indicates a relationship between the WVP of the zein film and the contact angle of the zein film. The mechanical properties of the zein film depended on the drying conditions during preparation. Zein films with various useful physical mechanical properties were produced.     

Influence of sorghum wax,glycerin, and sorbitol on physical properties of soy protein isolate films

Sorghum wax, sorbitol, glycerin, and soy protein isolate (SPI) composite films were prepared. Effects of sorghum wax, sorbitol, and glycerin concentrations on various films were evaluated using response surface methodology. All independent variables significantly (P<0.05) affected film water vapor permeability (WVP), tensile strength (TS), elongation at break (E), total color difference, and total soluble matter (TSM). Increasing the sorghum wax concentration decreased WVP and E. As sorbitol content increased in the composite films, WVP and TS increased. Sorbitol had a critical point of 2–5 g/5 g SPI for low values of TSM. The addition of sorbitol contributed more to the properties of the film than did glycerin.     

Preparation and characterization of chitosan/montmorillonite‐K10 nanocomposites films for food packaging applications

Chitosan (CS)/montmorillonite‐K10 (MMTK‐10) clay composite films with different amounts of the clay MMTK‐10 (0.5, 1, 2.5, and 5%) were prepared using a solution‐casting method, and their properties were determined. The objective of this study is to prepare CS/clay nanocomposites and then to investigate the effects of clay content on mechanical, barrier, and thermal properties of these nanocomposites. The prepared films were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction analysis, transmission electron microscopy, and scanning electron microscopy. Barrier properties (oxygen and water permeability), mechanical properties (tensile strength and elongation), and thermal behaviors (thermogravimetric analysis) were investigated and compared. The water vapor and gas permeability values of the composite films decreased significantly with increasing filler concentration. Tensile strength of the composites increased significantly with the addition of clay, and elongation at break decreased with increasing clay concentration. The tensile strength of nanocomposites is up to 34.82 MPa for 5 wt% clay content, and the tensile modulus shows a 74.63% higher value than that of neat CS. The resulting films had an opaque appearance, which depended on the amount of MMTK‐10 added. The oxygen permeability decreased with the increase in MMTK‐10. The minimum oxygen permeability (1.54 cm³/m² day atm) was recorded for film with 5% MMTK‐10. The water permeability of the composite films decreased significantly between 13 and 22% when clay was added. The dispersed clay improves the thermal stability and enhances the hardness and elastic modulus of the matrix systematically with the increased loading of clay. POLYM. COMPOS., 33:1874–1882, 2012. © 2012 Society of Plastics Engineers     

Water vapor barrier and mechanical properties of konjac glucomannan–chitosan–soy protein isolate edible films

The effects of polymer composition, glycerol concentration and pH of film-forming solution on water vapor permeability (WVP), tensile strength (TS) and percentage elongation at break (%E) of composite edible film based on konjac glucomannan (KGM), chitosan and soy protein isolate (SPI) were investigated. Of the plasticizers tested, glycerol was found to be a suitable plasticizer regarding mechanical properties and WVP. The WVPs of the films were determined to be (3.29–9.63) × 10^?11 g m^?1 s^?1 Pa^?1, TS between 16.77 and 51.07 MPa, and %E between 1.29% and 10.73%, depending on film composition. Incorporation of SPI to the polymer matrix decreased both WVP and mechanical properties. Increase in both glycerol concentration and the pH of film-forming solution decreased WVP and TS but increased %E. The results suggest that film composition and the pH of film-forming solution are the major factors influencing the film properties.     

环氧改性聚酰胺对淀粉基生物降解复合膜性能的影响

将环氧改性聚酰胺(EPA)与热塑性玉米淀粉复合后采用浇铸法制备出新型增强生物降解复合膜,研究了EPA对复合膜结晶性能、交联程度、力学性能以及生物降解性能的影响。结果表明,玉米淀粉与EPA、烷基烯酮二聚体及丙三醇复合后,结晶程度明显下降。当EPA质量分数为21 62%时,复合膜的交联度高达45 77%,且复合膜残留物中非EPA成分的质量分数也达到24 15%;复合膜的干态拉伸强度和断裂伸长率分别可以高于12 0MPa和45 0%,湿态拉伸强度和断裂伸长率则分别可以达到5 40MPa和30 0%以上。EPA的添加降低了复合膜的生物降解性能。