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以马铃薯淀粉为原料,以生物法对淀粉进行改性,普鲁兰酶可以专一性切开支链淀粉分支的α-1,6糖苷键提高直链淀粉含量,从而提高淀粉膜性能,同时以尿尿素为增塑剂,淀粉纳米晶(SNC)与纳米氧化锌(ZnO)为复合增强剂,采用流延法制备复合膜。以单因素试实验验 研究考察了增塑剂种类及用量、增强剂种类及用量对复合膜性能的影响。普鲁兰酶可以专一性切开支链淀粉分支的α-1,6糖苷键提高直链淀粉含量,从而提高淀粉膜性能。 以利用正交实验试验法探究淀粉酶解工艺,以复合膜的拉伸强度为指标,得到马铃薯淀粉的最佳酶解工艺为:酶用量0.8U/g,反应温度50℃,pHpH 4.0,反应时间2h。与未经酶处理的复合膜相比,马铃薯淀粉复合膜拉伸强度增加19%,断裂伸长率增加42.8%,透明度增加5.6%,雾度下降67.4%,水蒸气透过系数下降98.4%,透油系数下降52.6%。 相似文献
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首先对马铃薯淀粉进行乙酰化处理,然后采用共混法制备出乙酰化淀粉/壳聚糖复合膜,并分别考察了乙酸酐用量、壳聚糖用量、交联剂(乙二醛)用量、增塑剂(甘油)用量和反应温度等对复合膜性能的影响。研究结果表明:乙酰化淀粉可降低淀粉的结晶度,壳聚糖可改善复合膜的力学性能,甘油可改善复合膜的可塑性,乙二醛及PVA(聚乙烯醇)可提高复合膜的力学强度;当m(乙酸酐)=0.15 g、m(壳聚糖)=1.5 g、m(乙二醛)=0.3 g、V(甘油)=3 mL、V(PVA)=8 mL和反应温度为60℃时,复合膜的综合性能相对最好,其拉伸强度(8.55 MPa)相对最大。 相似文献
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用普鲁兰酶对马铃薯淀粉进行改性,以尿素为增塑剂,淀粉纳米晶(SNC)与纳米氧化锌(ZnO)为复合增强剂,采用流延法制备复合膜。以单因素实验考察了增塑剂种类及用量、增强剂种类及用量对复合膜性能的影响。以正交实验法探究淀粉酶解工艺,以复合膜的拉伸强度为指标,得到马铃薯淀粉的最佳酶解工艺为:酶用量0.8 U/g,反应温度50℃,pH=4.0,反应时间2 h。与未经酶处理的复合膜相比,马铃薯淀粉复合膜拉伸强度增加19.0%,断裂伸长率增加42.8%,透明度增加5.6%,雾度下降67.4%,水蒸气透过系数下降98.4%,透油系数下降52.5%。 相似文献
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针对环保复合胶会对建筑施工环保造成影响,提出了建筑施工中的新型环保复合胶工艺。以淀粉和聚乙烯醇作为基胶添加氧化剂、交联剂等提升复合胶性能,并通过调整淀粉、聚乙烯醇、双氧水等原料及添加剂的用量,试验制备出质量较好的新型环保复合胶。结果表明,淀粉用量为40%,1.2 mL双氧水,质量分数1.2%聚乙烯醇,硼砂用量为8 mL,过硫酸铵用量为0.33%,12%羧基丁腈胶乳配比下,新型环保复合胶的胶合强度较好,同时干燥时间与剥离强度都较高,硼砂用量与羧基丁腈胶乳用量还能有效提升新型环保复合胶的耐水性能。 相似文献
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水溶液聚合小麦淀粉接枝丙烯酸高吸水性树脂的研究 总被引:1,自引:0,他引:1
以小麦淀粉与丙烯酸为原料,以N,N′-亚甲基双丙烯酰胺为交联剂,过硫酸铵为引发剂,采用水溶液聚合法合成高吸水性复合树脂。考察了丙烯酸的中和度、淀粉/单体比例、引发剂、交联剂等对聚合反应和树脂性能的影响。通过正交试验优选出物料的最佳配比:丙烯酸的中和度为90%,引发剂用量为0.5%,交联剂用量为0.05%,淀粉含量为10%。制备得到的吸水性复合树脂吸水率达1060g.g-1,性能优于聚丙烯酸钠高吸水性树脂。 相似文献
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微水溶性缓释肥料用复合胶接材料的合成及性能研究 总被引:1,自引:0,他引:1
以淀粉、聚乙烯醇(PVA)和丙烯酸酯类单体为主要原料,采用交联反应法制备出水基可生物降解型胶接包膜材料,并重点阐述了淀粉、PVA和丙烯酸酯类单体用量对胶液及复合膜性能的影响。结果表明:当m(淀粉)=70 g、V(丙烯酸酯类单体)=V(5%PVA)=5 mL和m(交联剂)=2.5 g时,复合膜的透水、透气效果较佳,其吸水倍率和透水率分别为133%和16.97 g/(m2.h),并具有一定的可生物降解性能;该复合膜可用于半干旱地区微水溶性缓释肥料用胶接包膜材料的制备。 相似文献
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为了改善聚乙烯醇(PVA)膜的机械性能,选用玉米淀粉为原材料,50℃条件下以过硫酸铵和尿素为引发剂,同时加入丙烯酰胺对淀粉进行接枝改性,制备得到丙烯酰胺改性的玉米淀粉/PVA复合膜。其中,优化改性淀粉的接枝率确定最佳合成条件为淀粉/丙烯酰胺的质量比为3∶7、引发剂过硫酸铵占单体总质量的0.5%、尿素占单体总质量的0.5%。进一步利用优化的改性淀粉为改性剂,制备了系列改性玉米淀粉/PVA复合膜。采用傅里叶红外光谱、扫描电子显微镜(SEM)对复合膜的组成与结构进行表征,同时测定复合膜的机械性能、耐水性、耐热性等物化特性,结果表明30%ST-0.50%APSU改性淀粉的单体转化率为95.0%,接枝率为85.2%。 30%ST-0.50%APSU/PVA复合膜的耐热性能轻微下降,但断裂伸长率提高了256%,耐水性能提高了43.1%。 相似文献
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SA/PVA可降解复合塑料膜的制备与性能研究 总被引:1,自引:0,他引:1
对木薯原淀粉进行乙酰化改性,合成低酯化度的木薯淀粉醋酸酯(SA);经增塑、交联后与聚乙烯醇(PVA)合成可降解的SA/PVA复合塑料膜,重点研究了PVA、甘油、乙二醛的用量及SA的酯化度对复合膜力学性能的影响,并对复合膜性能进行了表征。结果表明:在PVA质量分数为40%,甘油质量分数为14%,乙二醛质量分数为4%时,可以得到力学性能较好的复合塑料膜;与原淀粉/PVA复合膜相比,复合膜致密性提高,玻璃化转变温度降低,结晶度下降,表现出更好的力学性能。 相似文献
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H. L. Abd El‐Mohdy 《应用聚合物科学杂志》2007,104(1):504-513
Starch‐based plastic films were prepared by the electron beam irradiation of starch and poly(vinyl alcohol) (PVA) in a physical gel state at room temperature. The influence of starch/PVA composition, irradiation dose, and plasticizer (glycerol) on the properties of the plastic films was investigated. The gel fraction of the starch/PVA films increased with both the radiation dose and PVA content in the plastic film and decreased with increasing glycerol concentration. The starch/PVA compatibility was determined by measurement of the thermal properties of the starch/PVA blends with various compositions with differential scanning calorimetry. The swelling of the starch/PVA films increased with increasing PVA content and decreasing irradiation dose. Mechanical studies were carried out, and the tensile strength of the films decreased at high starch ratios in the starch‐based mixture. This was due to the decrease in the degree of crosslinking of starch. Furthermore, when PVA, a biodegradable and flexible‐chain polymer, was incorporated into the starch‐based films, the properties of the films, such as the flexibility (elongation at break), were obviously improved. The tensile strength of the films decreased with increasing glycerol concentration, but elongation at break increased up to a maximum value at a 20% glycerol concentration, and then, it leveled off and decreased slightly. Biodegradation of the starch/PVA plastic films was indicated by weight loss (%) after burial in soil and morphological shape, which was detected by scanning electron microscopy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 504–513, 2007 相似文献
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Starch/polyvinyl alcohol (PVA) blend films were prepared by using corn starch, polyvinyl alcohol (PVA), glycerol (GL), and citric acid (CA) as additives and glutaraldehyde (GLU) as crosslinking agent for the mixing process. The additives, drying temperature, and the influence of crosslinker of films on the properties of the films were investigated. The mechanical properties, tensile strength (TS), elongation at break (% E), degree of swelling (DS), and solubility (S) of starch/PVA blend film were examined adding GL and CA as additives. At all measurement results, except for DS, the film adding CA was better than GL because hydrogen bonding at the presence of CA with hydroxyl group and carboxyl group increased the inter/intramolecular interaction between starch, PVA, and additives. CA improves the properties of starch/PVA blend film compared with GL. TS, % E, DS, and S of film adding GLU as crosslinking agent were examined. With increasing GLU contents, TS increases but % E, DS, and S value of GL‐added and CA‐added films decrease. When the film was dried at low temperature, the physical properties of the films were clearly improved because the hydrogen bonding was activated at low temperature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2554–2560, 2006 相似文献
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Recently, synthetic plastics are used widely in various fields, and with increased applications, disposal of waste plastics
has become a serious problem. Therefore, development of novel plastics that are degradable by microorganisms in soil has recently
been attracting much attention. In this study, starch/PVA-blended films were prepared from commercial starches with the different
amylose contents, PVA, and additives by using a simple mixing process and casting method. Glycerol (GL), sorbitol (SO), tartaric
acid (TA), and citric acid (CA) were used as additives. The physical properties such as tensile strength (TS), elongation
at break (%E), degree of swelling (DS), and solubility (S) with amylose contents of starches were investigated. The amylose
content of starches was analyzed by the colorimetric method. Thermal analysis of films was measured by using a differential
scanning calorimeter (DSC). Finally, biodegradability of the films was evaluated in a 6-month soil burial test. The examination
of the physical properties of biodegradable films indicates that with the higher amylose contents of starch used in preparing
the film, TS, and DS of films increased, whereas %E and S decreased. The additives containing both carboxyl and hydroxyl groups,
i.e. TA and CA, improved the physical properties of films. A thermal analysis of films revealed that the glass transition
temperature (T
g) rose because of the increased crystallization of films with the increasing the amylose contents. Also, films degraded rapidly
at the beginning and slow degradation took place until the experiment was completed. The films showed 50–80% degradation. 相似文献
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Starch/poly(vinyl alcohol) (PVA) films with the addition of 10 wt% CaCl2 and various content of glycerol were prepared. The effect of glycerol on the crystalline, thermal, and tensile properties of CaCl2‐doped starch/PVA films was studied by X‐ray diffraction, thermogravimetric analysis (TGA), and tensile testing, respectively. The effect of glycerol on the miscibility of CaCl2‐doped starch/PVA films was studied by scanning electron microscopy. The CaCl2‐doped starch/PVA film became more homogeneous after the addition of glycerol. The addition of glycerol would increase the crystallinity of CaCl2‐doped starch/PVA film. With the addition of 10 wt% glycerol and 10 wt% CaCl2, the starch/PVA film showed the highest degree of crystallinity. The TGA results show that the thermal stability of CaCl2‐doped starch/PVA film increased after the addition of glycerol. The toughness of CaCl2‐doped starch/PVA films was enhanced with the addition of glycerol. The starch/PVA film with the addition of 10 wt% CaCl2 and 20 wt% glycerol showed the tensile strength of 17 MPa and the elongation at break of 428%. Moreover, the water sorption of CaCl2‐doped starch/PVA film decreased after the addition of glycerol at the low and intermediate relative humidity of 33 and 54%. POLYM. COMPOS., 37:3191–3199, 2016. © 2015 Society of Plastics Engineers 相似文献
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