癸酸钠对淀粉与PVA混和浆液性能的影响

研究癸酸钠助剂对淀粉/PVA-1799黏附性能及浆膜性能的影响.通过与目标配方的对比,探索了淀粉取代PVA的可能性.试验结果表明:当癸酸钠用量为主浆料质量的1%时,淀粉/PVA共混浆料的黏附性能及浆膜性能都会显著提高;在使用癸酸钠时,随着淀粉用量的增加,共混浆膜的断裂强度增大,但断裂伸长率下降,耐屈曲次数减少,磨耗增加,对棉纤维的黏附性能提高.     

烷基羧酸及其钠盐对淀粉浆膜性能的影响

以浆膜的断裂强度、断裂伸长率、磨耗、耐屈曲次数为评价指标,评估了烷基羧酸及其钠盐对淀粉浆膜性能的影响.研究表明:对于烷基羧酸,当碳链在8～18之间时,淀粉浆料浆膜的断裂强度、断裂伸长率、耐屈曲次数随碳链长度减小而增加,磨耗减小.在相同的碳链长度下,烷基羧酸钠比烷基羧酸的使用效果好,其中,辛酸钠的效果最好,且w(辛酸钠)为2%(对淀粉浆料质量)时,淀粉浆膜的各项性能均较好.     

增塑剂对淀粉浆料性能的影响

针对淀粉浆膜脆硬,柔韧性差的缺点,将甘油、尿素、柠檬酸氢二铵等增塑剂分别以不同量加入淀粉中,并对浆膜的吸湿率、断裂强力、断裂伸长率、耐屈曲性及浆液粘附性等进行了测试分析。结果表明,使用增塑剂能改善淀粉浆膜的脆硬性能,且提高了淀粉对纯棉粗纱的粘附性;其中柠檬酸氢二铵对淀粉质量分数为1％时,对改善淀粉浆膜各项性能及纯棉粗纱粘附性的效用最大。     

甲氨酰乙基淀粉/PVA混合浆料性能的研究

研究了甲氨酰乙基淀粉与PVA1799浆料共混物的黏附性能及浆膜性能,并通过与目标配方的对比,探索了甲氨酰乙基淀粉取代PVA的可能性。实验表明,随着甲氨酰乙基淀粉含量的增加,共混浆膜的断裂强度增大,但断裂伸长率下降,磨耗增加,耐屈曲次数减少;同时对棉纤维的黏附性能提高,而共混比例对涤/棉纤维黏附性能的影响不大。与目前浆纱生产中常用的浆料配方相比较,甲氨酰乙基淀粉能够提高取代PVA的比例。     

氨基增塑剂对淀粉浆料的增塑作用

为满足无PVA浆料配方中对淀粉增塑作用的更高要求,以浆液黏度、黏度热稳定性、黏附性及浆膜性能为评价指标,研究几种氨基化合物对淀粉浆料的增塑作用.所研究的氨基化合物包括苯胺、一乙醇胺、尿素等,通过对比实验筛选出性价比较高的淀粉浆料增塑剂,探索合理的用量.结果表明:使用增塑剂能改善淀粉浆膜脆硬的属性,提高它的断裂伸长率和耐...     

羧甲基辐射淀粉浆料性能研究

研究利用辐射降解和羧甲基化制备的低黏度羧甲基淀粉的浆料性能.试验制备出了羧甲基辐射淀粉,并测试了不同黏度、取代度、纯度、pH值条件下,羧甲基辐射淀粉的浆液及浆膜性能.结果表明:羧甲基辐射淀粉具有高浓低黏浆料特征,其黏度热稳定性和成膜性能良好;随着黏度的下降,浆膜断裂强度和断裂伸长率降低;随着环境相对湿度的增加,断裂强度下降、断裂伸长率变大;随着取代度的增加,浆料黏度热稳定性提高,取代度在0.2～0.3范围内浆膜强度最大;浆膜性能随纯度的增加而改善;pH值在接近中性条件下,浆膜断裂强度较好.认为利用辐射降解和羧甲基化制备的低黏度羧甲基淀粉可用于纺织经纱上浆.     

氰乙基变性对淀粉浆料性能的影响

为了提高淀粉浆料的使用性能,以丙烯腈为醚化剂,通过改变丙烯腈对淀粉的投料比,制备了一系列具有不同取代度的氰乙基醚化淀粉。研究了氰乙基醚化变性方式及变性程度对纤维黏附性能和浆膜性能的影响。实验结果表明:淀粉氰乙基醚化变性能够改善淀粉对棉纤维的黏附性能,提高淀粉浆膜的断裂强度、断裂伸长率和耐屈曲次数,并能降低浆膜的磨耗;随着取代度的增加,氰乙基淀粉对棉纤维的黏附力先增大后减小,当取代度为0.047时,黏附力达到最大值;对涤纶纤维和涤/棉纤维而言,当取代度超过0.017时,黏附力随着取代度的增大而降低。     

高速剪切均质改善浆膜性能

为了进一步提高浆膜的性能,采用物理性的高速剪切均质加工方法对各种浆液进行处理,研究浆液高速剪切均质后浆膜性能的变化,探讨纯淀粉浆液、纯PVA浆液以及混合浆液经高速剪切均质后的浆膜性能。试验结果表明:高速剪切均质不仅能改善原淀粉的浆膜性能,更能较大幅度地提高混合浆膜的断裂强度、断裂伸长率、耐屈曲次数等物理机械性能,且在研究范围内剪切时间和剪切转速都与浆膜性能改善的程度成正相关。     

纤维素衍生物浆料性能的研究

为研究纤维素衍生物的浆料性能,对Finnfix10、Finnfix30的粘度特性、粘着力、浆膜强伸性、耐磨性、耐屈曲性、吸湿性及水溶性进行了测试,并与国产CMC、CMS、磷酸酯淀粉、醋酸酯淀粉、复合变性淀粉进行了对比.试验结果表明:纤维素衍生物对纯棉纱和涤棉混纺纱的粘附性都好;浆膜耐屈曲性好、水溶性好,断裂伸长率与原纱相近,适于作为经纱上浆主浆料使用.     

氧化羟丙基淀粉浆料性能研究

探讨氧化羟丙基淀粉浆料性能。利用氧化和羟丙基化复合变性制备了氧化羟丙基淀粉浆料,测试了黏度、取代度及pH值等因素对氧化羟丙基淀粉浆料及浆纱性能的影响。结果表明:氧化羟丙基淀粉浆料具有高浓低黏浆料特性,其黏度热稳定性和成膜性良好;在一定范围内,随着氧化剂用量的增加,黏度逐渐下降,浆膜断裂强度和断裂伸长率降低,耐磨性增加;随着取代度的增加,浆液黏度热稳定性提高,浆膜断裂强度和断裂伸长率都增加,水溶速度加快,浆液黏附力增大;取代度达到0.3的氧化羟丙基淀粉表现出良好的浆膜性能、黏附性能及对纯棉纱良好的浆纱效果。认为:取代度为0.3的氧化羟丙基淀粉具有较好的上浆性能。     

淀粉基纳米复合浆料与常用浆料性能对比

研究淀粉基纳米复合浆料的基本性能.通过测试淀粉基纳米复合浆料、聚酯浆料、PVA、氧化淀粉、醚化淀粉浆膜的机械性能,并分析对比其浆膜拉伸曲线.认为:虽然淀粉基纳米复合浆料浆膜的断裂强度较低,但由于其具有较高的断裂功和对涤纶纤维较好的黏附性,仍然为部分取代PVA创造了基础条件.指出:淀粉改性的方向是提高浆膜的断裂功,使普通淀粉由脆性材料转变为韧性材料;要进一步提高淀粉基纳米复合浆料的断裂强度,以达到完全取代PVA的目标.     

超声波改性马铃薯淀粉可降解性包装膜的制备研究

以超声波处理糊化的马铃薯淀粉为成膜原料,添加不同浓度的甘油作为增塑剂,海藻酸钠作为增强剂,通过测定膜的抗拉强度、水蒸汽透过性、CO2透过性,优选超声处理条件45min条件下,马铃薯淀粉浓度为9.0g/100mL,甘油含量为5.0g/100mL,海藻酸钠含量为0.6g/100mL。所制成的马铃薯淀粉膜抗拉强度、水蒸汽透过率、CO2透过率等指标可满足部分替代聚乙烯包装材料的要求。     

Mechanical and Thermal Characteristics of Pea Starch Films Plasticized with Monosaccharides and Polyols

Edible starch films were produced from pea starch and various plasticizers (mannose, glucose, fructose, and glycerol and sorbitol) at the ratio of 4.34, 6.50, 8.69, and 10.87 mmol plasticizer per gram of starch. After film specimens were conditioned at 50% relative humidity, mechanical properties (tensile strength, elongation, and modulus of elasticity), water vapor permeability (WVP), moisture content, and thermomechanical properties (G’ and tan8) were determined as a function of plasticizer concentration. At all concentration levels, monosaccharides (mannose, glucose, and fructose) made the starch films stronger (higher tensile strength) and more stretchable than polyols (glycerol and sorbitol), while WVP of monosaccharide‐plasticized starch films were lower than those of polyol‐plasticized starch films, especially at higher plasticizer concentration levels. Except for 4.34 mmol/g of mannose‐plasticized film, all the other films showed similar modulus of elasticity at the same plasticizer concentration. Polyol‐plasticized films had lower T than the monosaccharide‐plasticized films. Glucose‐ and sorbitol‐plasticized films needed more activation energy to go through glass transition than others. After all, research results showed that not only the polyols but also the monosaccharides were effective in plasticizing starch films. It is concluded that molecular size, configuration, total number of functional hydroxyl group of the plasticizer as well as its compatibility of the plasticizers with the polymer could affect the interactions between the plasticizers and starch molecules, and consequently the effectiveness of plasticization.     

挤压吹塑法制备淀粉基可食膜及其性能表征

以甘油为增塑剂,普兰多糖为黏合增强剂,采用熔融共混挤出技术制备热塑性淀粉,再挤出吹塑制备淀粉基可食膜。研究甘油对热塑性淀粉流变性、玻璃化转变温度、相变焓和微观形貌的影响;并研究了湿度环境对可食膜力学性能的影响及甘油对淀粉可食膜力学性能及热稳定性的影响。结果表明:甘油能有效的改善了热塑性淀粉的流变性和微观结构,降低热塑性淀粉的玻璃化转变温度,使淀粉结晶熔融焓变减小。实验制备的热塑性淀粉膜适宜在湿度40%的环境下使用;且在该湿度条件下,甘油添加量28%时,淀粉可食膜的纵向拉伸强度为5.26 MPa,断裂伸长率达到137.9%,横向拉伸强度为4.92 MPa,断裂伸长率为118.0%。     

Composition and Film Properties of Temperature Responsive,Hydrophobically Modified Potato Starch

The film‐forming properties of hydrophobically modified potato starch were studied to optimize coating and surface sizing formulations for improvement of barrier properties of paper and paperboard. The spontaneous fractionation of a potato starch hydrophobically modified with a quaternary dodecylammonium chloride resulted in an amylose‐rich precipitate with properties differing from those of the original starch. Film formation was investigated in the presence of glycerol and poly(vinyl alcohol) plasticizers. Anti‐plasticization was found to occur at low and intermediate plasticizer levels but highly flexible, continuous films were obtained when 30 parts of plasticizer were added to 100 parts of dry starch. The highest transparency and greatest flexibility were obtained with glycerol, while the hydrophobic film properties were maintained with poly(vinyl alcohol). A study of the glass transition temperatures and melting behavior of starch‐plasticizer films by differential scanning calorimetry gave useful information about the crystallinity of the films.     

酯化淀粉薄膜中增塑剂与淀粉分子间相互作用的研究

采用酯化淀粉以邻苯二甲酸二乙酯（DEP）为增塑剂,经流延法制备了酯化淀粉薄膜。通过扫描电子显微（SEM）、傅立叶变换红外光谱分析仪（FT-IR）、小角/广角X射线散射（SAXS/WAXS）等现代分析技术对酯化淀粉薄膜的结构及增塑剂DEP与淀粉分子间的相互作用变化进行了系统分析。结果表明,随着增塑剂DEP含量的增加,增塑剂DEP分子减弱了淀粉分子内/间相互作用力,且导致了无定形区域中淀粉分子形成部分排列更规整的微晶结构,促使淀粉分子形成有序微区,但有序微区结构尺寸Rg在37 nm~38 nm之间变化不大。通过调节酯化淀粉薄膜中增塑剂DEP含量,可控制增塑剂分子与淀粉分子间的相互作用、淀粉分子链段在薄膜中微区的有序排列程度及其规整程度,为设计抑制增塑剂迁移的酯化淀粉薄膜材料提供了基础数据。     

木素制可降解塑料的研究

以木质素、25%的甘油共混造粒,造粒后的木质素与淀粉母料、聚乙烯共混挤出制备55%的木质素基塑料.研究了木素/淀粉/聚乙烯共混物的流变特性、力学性能和降解性.流变特性表明共混物可加工性,添加淀粉母料的共混物的力学性能有所降低而降解性加快.     

Lipid Addition to Improve Barrier Properties of Edible Starch-based Films and Coatings

ABSTRACT: Effects of formulation (lipid presence, type of starch, and plasticizer) on microstructure, water vapor (WVP) and gas (GP) permeabilities of films and coatings were analyzed. Plasticizer was necessary to maintain film and coating integrity and to avoid pores and cracks. Films made from high amylose starch showed lower WVP and GP than regular corn starch films; permeabilities of films with sorbitol (20 g/L) were lower than those with glycerol. The addition of 2g/L sunflower oil to the formulations decreased WVP of starch-based films; X-ray diffraction and Differential Scanning Calorimetry experiments demonstrated that films with plasticizer and lipid showed lower crystalline-amorphous ratio compared to films without additives. Microstructural observations helped explain the decrease of the film permeabilities during storage.