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Montmorillonite (MMT) and organically modified montmorillonite (OMMT) were utilized to reinforce the thermoplastic acetylated starch (TPAS) composite prepared with glycerol as a plasticizer. After the addition of layered silicates, the restriction of the motion of the intercalated acetylated starch molecular chains by the clay layer sheets led to an increase in melt viscosity and equilibrium torque. As expected, the tensile strength and storage modulus of the TPAS composite were remarkably enhanced due to the interaction of layered silicates with the TPAS matrix, but the thermal stability of the TPAS composite was not obviously improved. The greater reinforcing effect of OMMT than that of MMT could be attributed to the better dispersion of OMMT in the TPAS matrix, resulting from the larger distance between OMMT layers after the modification by organic ammonium cations with long alkyl chains. 相似文献
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影响可食性淀粉膜性能的因素研究 总被引:4,自引:1,他引:4
鉴于传统塑料包装材料的环境压力日益增强,开发可降解的包装材料就成为当前科技攻关的重点。可食性淀粉膜是可降解薄膜中发展前景最为广阔的产品之一。但是当前可食性淀粉薄膜的机械强度、热封性、耐水性等方面还与合成薄膜材料有一定的差距,这也是其市场化的难点所在。因此,文中综述了影响可食性淀粉膜性能的主要因素,希望能为进一步加快可食淀粉膜的深层技术开发和产品早日面市和大规模应用提供一定的技术支持。 相似文献
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In this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for corn starch to prepare thermoplastic starch (EPTPS). FT‐IR spectra showed that the absorption bands of the C‐O groups of the starch molecules were shifted to lower wavenumbers, which indicated that a strong and stable hydrogen bond had been formed between ethylenebisformamide and starch. By scanning electron microscope (SEM) native individual corn starch granules were proved to transfer to a continuous phase. The crystallinity of native corn starch, GPTPS (glycerol plasticized corn starch) and EPTPS was characterized by X‐ray diffraction (XRD). Water resistance of EPTPS was better than that of GPTPS. It decreased from 50.2% for GPTPS to 37.8% for EPTPS. The mechanical analysis showed that elongation at break increased markedly, being 260% for the EPTPS containing 35% (w/w) ethylenebisformamide. Thermal stability of GPTPSs and EPTPSs was also determined by thermogravimetric analysis (TGA). The glass transition temperature Tg, as measured by dynamic mechanical thermal analysis (DMTA), of EPTPS was higher than that of GPTPS. 相似文献
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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... 相似文献
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N,N‐Bis(2‐hydroxyethyl)formamide (BHF) was synthesized efficiently and used as a new plasticizer for corn starch to prepare thermoplastic starch (TPS). The hydrogen bond interaction between BHF and starch was proven by Fourier‐transform infrared (FT‐IR) spectroscopy. As detected by scanning electron microscopy (SEM), starch granules were completely disrupted and a continuous phase was obtained. The crystallinity of corn starch and BHF‐plasticized TPS (BTPS) was characterized by X‐ray diffraction (XRD). The thermal behavior of glycerol‐plasticized TPS (GTPS) and BTPS was investigated by differential scanning calorimetry (DSC). The water resistance of BTPS was better than that of GTPS. Generally, at low relative humidity (RH), the tensile strength of BTPS was higher than that of GTPS. At high RH, the elongation at break of BTPS was higher than that of GTPS. 相似文献
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以甘油、乙二醇、山梨醇和壳聚糖为塑化剂,机械活化柠檬酸淀粉酯为原料,以断裂伸长率为评价指标,通过SEM、FT-IR、TGA和接触角的分析,探讨不同塑化剂对淀粉酯成膜性能的影响。结果表明,不同塑化剂对淀粉酯的影响不同。不同塑化剂对淀粉酯膜的断裂伸长率影响为甘油>山梨醇>乙二醇>壳聚糖>原淀粉。添加塑化剂能使淀粉酯更好地成膜。SEM分析表明,以甘油和壳聚糖为塑化剂的淀粉酯膜具有更多网状结构,表面透气性好;以乙二醇和山梨醇为塑化剂的淀粉酯膜更为致密,表面相对光滑,气密性更好。FT-IR表明,淀粉酯膜均成功塑化且具有相同峰型,说明不同塑化剂的塑化机理基本相同。TGA显示,热分解温度与塑化剂分子大小及羟基含量存在密切关系。接触角分析表明,不同塑化剂对于淀粉酯膜的亲水性各不相同,其亲水性大小为山梨醇>甘油>壳聚糖>乙二醇。 相似文献
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A simple and environmentally‐friendly processing method was used to prepare thermoplastic starch (TPS)/ montmorillonite (MMT) nanocomposites. X‐ray diffraction (XRD) and transmission electron microscopy (TEM) demonstrated that glycerol could enlarge the d‐spacing and destruct the layered structure of MMT effectively during the pre‐processing of MMT. So the enlarged d‐spacing and fragmentized platelets of glycerol activated‐MMT were a precondition to form intercalated or exfoliated TPS‐based nanocomposites during the melt extrusion processing. These highly dispersive and compatible TPS/activated‐MMT nanocomposites had increased thermal stability and tensile properties as compared with non‐activated composites. Especially, the tensile strength of nanocomposites could be enhanced to 8.6 MPa, the improvement was about two times the initial tensile strength of TPS. 相似文献
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Mahafooj Alee Jun Fu Qingfei Duan Mao Yang Hongsheng Liu Jian Zhu Bao Xianyang Ling Chen Long Yu 《Starch - St?rke》2023,75(11-12):2300059
The effectiveness of various alcohols as plasticizers for starch-based materials is studied. Specifically, the impact of molecular structures, such as the number of hydroxyl groups, molecular weights, and chemical structures of these compounds, on the performance of starch-based films is studied. Several alcohols are used, including mono-alcohols (propanol, butanol, pentanol, and hexanol), di-alcohols (ethylene glycol, propanediol, butanediol, and pentanediol), and polyols (glycerol, erythritol, xylitol, sorbitol). Tensile testing and DSC, TGA, DMA, XRD, and SEM characterization of the starch film are used to assess plasticizing effectiveness. Alcohols with a low number of ─OH groups, such as mono-alcohols, are not retained in the starch matrix because their compatibility with starch is low. The presence of a long alkyl chain in the alcohol reduces compatibility with the starch matrix even more. This type of material has low or no plasticizer efficiency. Di-alcohols are more compatible with starch, especially those with short alkyl chains like ethylene glycol. Polyols with many ─OH groups are more compatible with starch. The effectiveness of these alcohols as starch plasticizers is proportional to the number of ─OH groups present. All alcohols, whether liquid or solid, must facilitate water′s action. 相似文献
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本文以蜡质玉米淀粉为原料,经普鲁兰酶酶解脱支,短直链淀粉重结晶制取淀粉纳米颗粒(SNPs)。采用差示扫描量热仪(DSC)和动态流变仪,探究了不同浓度SNPs在甘油、山梨糖醇、葡萄糖水溶液中的热特性、回生特性以及流变特性的变化规律。DSC测试表明,添加山梨糖醇、葡萄糖和甘油溶液(其与水比例为1:1)后,SNPs的起始糊化温度分别增加了10.85℃、10.96℃和15.02℃,SNPs的终止糊化温度分别增加了9.29℃、9.17℃、12.40℃。回生结果表明,增塑剂会抑制SNPs的回生。随着浓度增加,SNPs在增塑剂体系中储能模量明显增加,且损耗模量大于储能模量,凝胶性增强。20%SNPs在山梨糖醇溶液和甘油溶液中的储能模量是10 Pa·s左右,而在葡萄糖溶液中大于1000 Pa·s,在葡萄糖溶液中损耗模量在100~500 Pa·s,说明SNPs葡萄糖水溶液具有更强的凝胶性。本文为SNPs在不同增塑剂中制备可降解膜提供理论依据。 相似文献
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Camila da Silva Figueiró;Carmen Iara Walter Calcagno;Ruth Marlene Campomanes Santana; 《Starch - St?rke》2024,76(3-4):2300012
Short-life packaging has been contributing to the increased consumption of polymers. Expanded polystyrene (EPS) is a material that is widely used in disposable packaging, however, its residue occupies a large volume, is difficult to degrade, and its recycling is expensive. That's why the interest in looking for a material of natural and biodegradable origin that can be an alternative to petrochemical-based polymers. One possibility would be starch, which is a natural and biodegradable polysaccharide and can be extracted from different sources. However, natural starch does not have good properties for commercial application, requiring chemical modifications and/or the incorporation of additives. This article carried out a compilation of current studies that work on the development of packaging, whether film or foams, based on plasticized starch (TPS), and analyzes the influence of the incorporation of additives or treatments carried out in the starch. The blowing agent decreases foam density, cell size, and increases cell density. Incorporation of glycerol in starch foams increases the gelatinization temperature, decreases viscosity and resistance to expansion. The surfactant decreases the density and moisture absorption of the foam, the nucleating agent acted by increasing the mechanical strength and density of the foam, and decreases the absorption of water. 相似文献
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ABSTRACT: Tensile strength (TS), elongation (E), water vapor permeabilities (WVP) and solubilities were determined for highly carboxymethylated starch (HCMS)-based edible films plasticized with sorbitol (S), xylitol (X), mannitol (M) and glycerol (G). TS and E of HCMS-based film increased as the concentration of plasticizer S, M or × increased. TS of the HCMS-based film containing combined plasticizers were higher than those of films containing single plasticizer. The WVP of HCMS-based films seemed to decreased as the concentration of M, X or G plasticizer increased. Increasing plasticizer concentrations in HCMS-based film resulted in decreasing solubility of the films. 相似文献
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旨在为浓香花生油的品质提升和安全生产提供科学指导,以4种市售淀粉(普通淀粉、乙酰化二淀粉磷酸酯、羟丙基二淀粉磷酸酯、醋酸酯淀粉)为吸附剂,浓香花生油中邻苯二甲酸二(2-乙基)己酯(DEHP)脱除率为衡量指标,研究了淀粉吸附剂种类、添加量、添加位置、添加方式及浓香花生油添加量对浓香花生油中DEHP的脱除效果,并考察了淀粉吸附剂对浓香花生油品质的影响。结果表明:4种市售淀粉吸附剂对DEHP的脱除能力大小依次为醋酸酯淀粉>羟丙基二淀粉磷酸酯>乙酰化二淀粉磷酸酯>普通淀粉;采用在烘炒前添加醋酸酯淀粉吸附剂至花生仁中的吸附脱除方法,在浓香花生油添加量1%、醋酸酯淀粉添加量2%的条件下,DEHP的脱除率为354%;在烘炒前添加醋酸酯淀粉吸附剂DEHP的脱除效果好于烘炒后添加的,且直接将醋酸酯淀粉吸附剂添加于浓香花生油中无明显DEHP脱除效果;醋酸酯淀粉对浓香花生油酸值、过氧化值、色泽、透明度及风味无明显影响。综上,在花生仁烘炒前添加醋酸酯淀粉吸附剂,可以减少浓香花生油中DEHP含量,从而保证浓香花生油的产品品质。 相似文献
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非明胶软胶囊囊材研究进展 总被引:3,自引:0,他引:3
软胶囊作为保健食品和药品常用的剂型,具有生物利用度高、易于吞咽、掩味性好、适用范围广和外形美观等优点。本文综述了近年来国内外非明胶软胶囊囊材的研究进展,包括淀粉、食用胶和高分子聚合物等主要材料以及增塑剂等辅料的特性及应用,为新型软胶囊的开发应用提供参考。 相似文献