Rheological behavior

流变行为
  • 文章类型: Journal Article
    可以使用不同的交联剂来设计和优化水凝胶特征以满足特定的要求。在这方面,本工作研究了纤维素基水凝胶的物理化学特征,通过使用来自相同缩水甘油家族的不同环氧交联剂设计,即环氧氯丙烷(ECH),1,4-丁二醇二缩水甘油醚(BDDE),和三羟甲基丙烷三缩水甘油醚(TMPTGE)。交联剂的结构(从简单到支化)和官能度(单,研究了水凝胶的双环氧基团和三环氧基团)特征。通过凝胶分数研究了水凝胶的性能,以及ATR-FTIR,DVS,SEM,DSC,和TG分析。此外,研究了水凝胶的溶胀和流变行为。讨论了每种方法的优点和局限性,并建立了交联剂结构与水凝胶性能之间的强相关性。通过ATR-FTIR光谱证明了新醚键的形成。强调的是,孔径直接受交联剂类型的影响,即,它随着交联剂分子中环氧基团数量的增加而减少,即,从46±11.1µm(水凝胶CE,使用ECH)至12.3±2.5µm(水凝胶CB,使用BDDE)和6.7±1.5µm(水凝胶CT,用TMPTGE)。流变行为与溶胀数据和水凝胶形态一致,例如具有最高Qmax和最大孔径的CE比CB和CT相对更具弹性。相反,通过使用具有更复杂结构的交联剂获得的更致密的基质具有更好的热稳定性。实验结果突出了使用特定交联剂的可能性,具有定义的结构和功能,为了确定水凝胶的主要特性,含蓄地,为某个应用领域设计它们。
    Hydrogel features can be designed and optimized using different crosslinking agents to meet specific requirements. In this regard, the present work investigates the physico-chemical features of cellulose-based hydrogels, designed by using different epoxy crosslinkers from the same glycidyl family, namely epichlorohydrin (ECH), 1,4-butanediol diglycidyl ether (BDDE), and trimethylolpropane triglycidyl ether (TMPTGE). The effect of the crosslinker\'s structure (from simple to branched) and functionality (mono-, bi- and tri-epoxy groups) on the hydrogels\' features was studied. The performances of the hydrogels were investigated through the gel fraction, as well as by ATR-FTIR, DVS, SEM, DSC, and TG analyses. Also, the swelling and rheological behaviors of the hydrogels were examined. The advantages and limitations of each approach were discussed and a strong correlation between the crosslinker structure and the hydrogel properties was established. The formation of new ether bonds was evidenced by ATR-FTIR spectroscopy. It was emphasized that the pore size is directly influenced by the crosslinker type, namely, it decreases with the increasing number of epoxy groups from the crosslinker molecule, i.e., from 46 ± 11.1 µm (hydrogel CE, with ECH) to 12.3 ± 2.5 µm (hydrogel CB, with BDDE) and 6.7 ± 1.5 µm (hydrogel CT, with TMPTGE). The rheological behavior is consistent with the swelling data and hydrogel morphology, such as CE with the highest Qmax and the largest pore size being relatively more elastic than CB and CT. Instead, the denser matrices obtained by using crosslinkers with more complex structures have better thermal stability. The experimental results highlight the possibility of using a specific crosslinking agent, with a defined structure and functionality, in order to establish the main characteristics of hydrogels and, implicitly, to design them for a certain field of application.
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  • 文章类型: Journal Article
    在本研究中,非常规和绿色技术(超声处理)被用来从小,回收生物活性化合物,中型和大型脱脂枣种子粉(DDSP)颗粒。将从DDSP中回收的生物活性化合物和剩余的富含纤维的残余物作为功能性成分掺入饼干面团中,以增强面团和饼干的功能性和质量特性。多酚提取物和2.5%,5%和7.5%的富含纤维的提取残留物的取代水平被纳入配方,然后研究对流变学的影响,面团和饼干的物理和微观结构特性。损耗和储能模量,G\'\'和G\',分别,面团的含量随颗粒尺寸的减小和取代水平的增加而增加,而tanδ随富纤维提取残渣的取代水平的增加而降低。在7.5%取代水平下的最小颗粒导致面团中的最低蠕变应变值。面团和饼干的硬度随着颗粒尺寸的减小和残留物取代水平的增加而增加。最小粒度的7.5%取代水平导致最暗的面团和饼干。饼干的铺展比和直径随着残留物替代水平的增加而降低。在用7.5%取代水平的最大粒度取代的饼干中观察到50.61mm的最小直径和8.36的铺展比。面团和饼干的微观结构图像显示,掺入富含纤维的提取残留物破坏了面筋网络的连续性。这项研究为使用绿色超声技术从日期副产品中提取生物活性成分提供了有价值的见解,并利用这些化合物来改善烘焙产品的功能属性,作为衡量日期副产品价值的可持续方法。
    In the present study, non-conventional and green technology (ultrasonication) was utilized to recover bioactive compounds from the small, medium and large sized defatted date seed powder (DDSP) particles. Bioactive compounds recovered from DDSP and the remaining fiber-rich residue were incorporated as functional ingredient in the biscuit dough to enhance the functionality and the quality characteristics of the dough and biscuit. The polyphenolic extract and 2.5 %, 5 % and 7.5 % substitution levels of fiber-rich extraction residue were incorporated in formulations followed by investigating the effect on rheological, physical and microstructural properties of dough and biscuit. Loss and storage moduli, G\'\' and G\', respectively, of dough increased with decreasing particle size and increasing substitution level while tan δ decreased with increasing substitution level of fiber-rich extraction residue. The smallest particles at 7.5 % substitution level resulted in the lowest creep strain value in dough. Hardness of the dough and biscuit increased with decreasing particle size and increasing substitution level of the residue. The 7.5 % substitution level of the smallest particle size resulted in the darkest dough and biscuit. Spread ratio and diameter of the biscuit decreased with increasing substitution level of the residue. The smallest diameter of 50.61 mm and spread ratio of 8.36 was observed in the biscuits substituted with the largest particle size with 7.5 % substitution level. Microstructural images of dough and biscuit revealed that the continuity of the gluten network was disrupted by the incorporation of the fiber-rich extraction residue. This study provided valuable insights into extracting bioactive components from date by-products using green ultrasonication technique and utilizing such compounds to improve functional attributes of bakery products, as a sustainable approach for valorizing date by-products.
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  • 文章类型: Journal Article
    巴氏灭菌,作为食品加工的重要组成部分,Pickering乳液稳定性的调节越来越受到关注。在这项研究中,研究了巴氏杀菌和魔芋葡甘露聚糖(KGM)在Pickering乳液性能调节中的作用。结果表明,KGM形成的网络结构抑制了巴氏杀菌引起的液滴团聚,提高了Pickering乳液的热稳定性。KGM浓度的增加改善了其网络结构的致密化,如巴氏灭菌后乳液的粘弹性增强所证明的。在65°C巴氏灭菌30分钟后,包裹在Pickering乳液中的β-胡萝卜素的保留率可以达到99%。此外,巴氏杀菌进一步增强了KGM对游离脂肪酸释放的抑制作用,并实现了β-胡萝卜素的可控释放。该研究为构建用于递送温度敏感疏水成分的高度稳定的Pickering乳液提供了理论指导。
    Pasteurization, as a meaningful part of food processing, has received growing attention for regulating Pickering emulsion stability. In this research, the role of pasteurization and konjac glucomannan (KGM) in the modulation of Pickering emulsion properties was investigated. The results showed that the network structure formed by KGM inhibited the agglomeration of droplets due to pasteurization, which improved the heat stability of the Pickering emulsion. Increasing the concentration of KGM improved the densification of its network structure, as evidenced by the enhanced viscoelasticity of the emulsion after pasteurization. The retention rate of β-carotene encapsulated in the Pickering emulsion could reach 99% after pasteurization at 65 °C for 30 min. Moreover, pasteurization further enhanced the inhibitory effect of KGM on free fatty acid release and implemented a manageable release of β-carotene. This research offers theoretical guidance for the construction of highly stable Pickering emulsions for delivering temperature-sensitive hydrophobic ingredients.
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  • 文章类型: Journal Article
    黑色素瘤,主要由太阳紫外线(UV)辐射引起,可以通过使用防晒霜来防止。然而,合成防晒霜的使用引起了环境问题。具有抗氧化光保护特性和对癌细胞的细胞毒性作用的天然化合物有望用于预防和治疗具有较小环境影响的黑素瘤。这项研究的重点是白千层精油(EO)的光保护和抗肿瘤应用。从M.leucadendron叶中加氢蒸馏EO,收率为0.59%。气相色谱-质谱法检测单萜和倍半萜。使用相转化法制备具有(NE-EO)和不具有EO(NE-B)的纳米乳液,表现出良好的稳定性,球形或椭圆形形态,和假塑性轮廓。通过分光光度法评估的光保护活性表明,NE-EO比NE-B和游离EO更有效。通过DPPH和ABTS方法评估的抗氧化活性表明,纯的和纳米乳化的EO主要抑制ABTS自由基,显示IC5040.72和5.30µg/mL,分别。对L-929小鼠成纤维细胞的细胞毒性试验,NGM人类黑素细胞,B16-F10黑色素瘤,和MeWo人黑色素瘤显示EO和NE-EO对黑色素瘤细胞的细胞毒性高于非肿瘤细胞。稳定的NE-EO显示出预防和治疗黑素瘤的潜力。需要进一步的研究才能更好地了解这些活动。
    Melanoma, primarily caused by solar ultraviolet (UV) radiation, can be prevented by the use of sunscreens. However, the use of synthetic sunscreens raises environmental concerns. Natural compounds with antioxidant photoprotective properties and cytotoxic effects against cancer cells can be promising for the prevention and treatment of melanoma with less environmental effect. This study focuses on Melaleuca leucadendron essential oil (EO) for photoprotection and antitumor applications. EO was hydrodistilled from M. leucadendron leaves with a 0.59% yield. Gas chromatography-mass spectrometry detected monoterpenes and sesquiterpenes. Nanoemulsions were prepared with (NE-EO) and without EO (NE-B) using the phase inversion method, showing good stability, spherical or oval morphology, and a pseudoplastic profile. Photoprotective activity assessed spectrophotometrically showed that the NE-EO was more effective than NE-B and free EO. Antioxidant activity evaluated by DPPH and ABTS methods indicated that pure and nanoemulsified EO mainly inhibited the ABTS radical, showing IC50 40.72 and 5.30 µg/mL, respectively. Cytotoxicity tests on L-929 mouse fibroblasts, NGM human melanocyte, B16-F10 melanoma, and MeWo human melanoma revealed that EO and NE-EO were more cytotoxic to melanoma cells than to non-tumor cells. The stable NE-EO demonstrates potential for melanoma prevention and treatment. Further research is required to gain a better understanding of these activities.
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  • 文章类型: Journal Article
    为评价复合聚合物改性沥青的热稳定性,热塑性弹性体丁苯橡胶(SBR)/聚丙烯(PP)颗粒使用热熔共混技术制备,以丁基橡胶粉和废聚丙烯颗粒为原料。采用频率扫描试验和多应力蠕变恢复(MSCR)试验,研究了不同评价指标对SBR/PP改性沥青热稳定性的影响,使用Cole-Cole图和微观结构图像研究了SBR/PP颗粒与沥青的相容性。测试表明,首先,加入SBR/PP热塑性弹性体可以提高沥青的性能等级(PG)等级,增强沥青在高低温环境下的适应性,评价分离指标能更合理地反映复合改性沥青的高温储存稳定性。此外,胶塑比越大,复合改性沥青的高温热稳定性越差。此外,在复合颗粒中加入添加剂可以促进SBR/PP颗粒在沥青中更均匀地分散,形成更理想的微观结构,提高复合改性沥青的热稳定性。最终,Cole-Cole图的半圆形曲线可以反映SBR/PP改性沥青两相结构的相容性特征,可作为评价聚合物改性沥青相容性的辅助指标。
    To evaluate the thermal stability of composite polymer-modified asphalt, thermoplastic elastomer styrene-butadiene rubber (SBR)/polypropylene (PP) pellets were prepared using a hot-melt blending technique, with butyl rubber powder and waste polypropylene pellets as raw materials. The effects of different evaluation indexes on the thermal stability of SBR/PP-modified asphalt were investigated using a frequency scan test and a multi-stress creep recovery (MSCR) test, and the compatibility of SBR/PP particles with asphalt was studied using the Cole-Cole diagram and microstructure images. The tests show that, firstly, the performance grade (PG) classification of asphalt can be improved by adding an SBR/PP thermoplastic elastomer to enhance the adaptability of asphalt in high- and low-temperature environments, and the evaluation separation index can reflect the high-temperature storage stability of composite-modified asphalt more reasonably. Additionally, the larger the rubber-to-plastic ratio the worse the high-temperature thermal stability of composite-modified asphalt. Moreover, the addition of additives to the composite particles can promote the SBR/PP particles in the asphalt to be more uniformly dispersed, forming a more desirable microstructure and improving the thermal stability of composite-modified asphalt. Ultimately, the semicircular curve of the Cole-Cole diagram can reflect the compatibility characteristics of the two-phase structure of SBR/PP-modified asphalt, which can be used as an auxiliary index to evaluate the compatibility of polymer-modified asphalt.
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  • 文章类型: Journal Article
    全球食品市场的多样性正在扩大,每年都有数千种新产品进入市场,其中营养和功能食品占据重要地位。本研究工作针对三种药材的营养评价,即,姜黄(姜黄L.),姜(生姜),和黑孜然(Nigellasativa)。面包制剂富含这些草药的单独/组合补充剂(1-3%)。稍后,对面包进行了营养分析,流变学,纹理,和感官特征。结果表明,这些草药改善了面包的营养成分,尤其是灰分和纤维,作为最大灰分和纤维含量被注意到在T15(2.0%干燥粉末的每个植物)的值1.64±0.04%和4.63±0.16%,分别。有关流变行为的结果表明,流变特性的变化很小,并且面团发育时间从T0的2.80±0.13分钟略微增加到T10的4.50±0.20分钟。感官属性还表明其明显的适用性,因为添加草药对外部和内部特征的影响最小。虽然一些参数,如地壳和面包屑的颜色受到了黑孜然添加的影响,分别为6.25±0.52和4.44±0.19,在T15中,添加生姜会影响香气特征,以低剂量补充草药的组合减轻了其他草药的不利影响。此外,延长保质期,特别是加入姜黄粉,是这项研究的标志.这项研究得出结论,可以将草药掺入烘焙产品中,以改善功能性草药面包的营养和感官属性。
    The diversity in the global food market is expanding as thousands of new products enter the business every year, among which nutraceutical and functional foods hold important positions. The present research work aimed at the nutritional evaluation of three medicinal herbs, i.e., turmeric (Curcuma longa L.), ginger (Zingiber officinale), and black cumin (Nigella sativa). A bread formulation was enriched with the individual/combined supplementation (1-3%) of these herbs. Later, the bread was analyzed for nutritional, rheological, textural, and sensorial characteristics. The results revealed that the herbs improved the nutritional composition of bread, especially ash and fiber, as the maximum ash and fiber contents were noticed in T15 (2.0% dried powder of each plant) with values of 1.64 ± 0.04% and 4.63 ± 0.16%, respectively. The results regarding the rheological behavior showed minor variations in the rheological traits and a slight increase in dough development time up to 4.50 ± 0.20 min in T10 from 2.80 ± 0.13 min in T0. The sensorial attributes also indicated their marked suitability as external and internal characteristics were least affected by the addition of the herbs. Although some parameters like the crust and crumb colors were affected by the addition of black cumin, showing values of 6.25 ± 0.52 and 4.44 ± 0.19, respectively, in T15, and aroma characteristics were affected by the addition of ginger, supplementation with a combination of herbs at lower doses mitigated the adverse effects of other herbs. Moreover, shelf-life extension, especially with the addition of turmeric powder, was the hallmark of this research. This study concluded that medicinal herbs can be incorporated into baked products to improve the nutritional and sensorial attributes of functional herbal bread.
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  • 文章类型: Journal Article
    本研究旨在使用折射窗干燥(RWD)系统生产干燥的tarhana。干燥过程也在真空下进行;目前的研究是文献中的第一个。使用不同的加热介质,最高温度可以调整到高于RWD研究中使用的水平。考虑到结果,与对照组(烘箱和热风干燥机)相比,RWD的工艺时间节省超过85%和75%,分别。在RWD中干燥的Tarhana样品在真空条件下也比在大气条件下更快(50%)。在大气条件下通过RWD在110°C干燥的样品中,总酚含量(TPC)和总抗氧化活性(TAA)的最高保存率。技术物理性能优于对照组。tarhana汤的流变行为类似于假塑性流动行为,并由幂律和Herschel-Bulkey模型明确定义。总之,RWD可以是tarhana生产的有前途的技术。
    This study aimed to produce dried tarhana using a refractance window drying (RWD) system. The drying process was also carried out under vacuum; the current study is the first in the literature. Using different heating mediums, the maximum temperature can be adjusted to a level above that used in RWD studies. Considering results, process time savings in RWD were over 85% and 75% compared to control groups (oven and hot air dryer), respectively. Tarhana samples dried in RWD were also faster (50%) under vacuum conditions than atmospheric ones. The highest preservation of total phenolic content (TPC) and total antioxidant activity (TAA) was for samples dried by RWD at 110°C under atmospheric conditions. Techno-physical properties were better than the control group. The rheological behavior of tarhana soups was similar to pseudoplastic flow behavior and well defined by the Power law and Herschel-Bulkey models. In conclusion, RWD can be a promising technique for tarhana production.
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  • 文章类型: Journal Article
    由于半结晶聚酯(乳酸)(PLA)与其他增强材料结合使用,相分离等挑战,环境污染,制造困难可能会阻碍解放军的利益,包括完全的生物降解性和强大的机械性能。在目前的调查中,熔融共混用于建立低分子量和高分子量聚乳酸(LPLA和HPLA)的混合物。结晶度,流变学,使用旋转流变仪对组合物的力学性能进行了分析,差示扫描量热法,X射线衍射,偏振光学显微镜,扫描电子显微镜,和通用测试设备。结果表明LPLA和HPLA之间的相容性。此外,LPLA浓度的增加导致结晶速率的降低,球晶尺寸,分数结晶度,等温结晶过程中的XRD峰强度。LPLA在等温结晶过程中充当稀释剂,而HPLA在非等温结晶过程中充当成核剂,促进LPLA晶体的生长并导致共结晶。具有5%LPLA质量分数的共混体系表现出最高的拉伸强度并增强流变特性。通过有效地利用PLA的各种分子量之间的关系,流变学,和结晶行为,这种审查改善了材料的物理和机械特性,开辟新的机遇。
    As semi-crystalline polyester (lactic acid) (PLA) is combined with other reinforcing materials, challenges such as phase separation, environmental pollution, and manufacturing difficulties could hinder the benefits of PLA, including complete biodegradability and strong mechanical properties. In the present investigation, melt blending is utilized to establish a mixture of low- and high-molecular-weight polylactic acids (LPLA and HPLA). The crystallinity, rheology, and mechanical properties of the combination were analyzed using rotational rheometry, differential scanning calorimetry, X-ray diffraction, polarized optical microscopy, scanning electron microscopy, and universal testing equipment. The results demonstrate compatibility between LPLA and HPLA. Moreover, an increase in LPLA concentration leads to a decrease in the crystallization rate, spherulite size, fractional crystallinity, and XRD peak intensity during isothermal crystallization. LPLA acts as a diluent during isothermal crystallization, whereas HPLA functions as a nucleating agent in the non-isothermal crystallization process, promoting the growth of LPLA crystals and leading to co-crystallization. The blended system with a 5% LPLA mass fraction exhibits the highest tensile strength and enhances rheological characteristics. By effectively leveraging the relationship between various molecular weights of PLA\'s mechanical, rheological, and crystallization behavior, this scrutiny improves the physical and mechanical characteristics of the material, opening up new opportunities.
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  • 文章类型: Journal Article
    化学合成的聚合物聚丙烯酰胺(HPAM)在常规油藏中取得了优异的驱油效果,但其在极端油藏环境下的驱油能力较差。开发适用于极端储层条件的生物聚合物驱油剂,三种生物聚合物的粘度变化和流变特性,Diutan口香糖,黄原胶,和scleroglucan,在极端储层条件下进行了研究(高盐,高温,强酸,和碱),以及温度的影响,矿化,pH值,等因素对其粘度和长期稳定性进行了分析比较。结果表明,三种生物聚合物在90°C及以下的温度下具有最佳的增粘能力。三种生物聚合物的粘度为80.94mPa·s,11.57mPa·s,和59.83mPa·s,分别,当浓度为1500mg/L,盐度为220g/L时。在250s-1的剪切速率下,100°C〜140°C,硬葡聚糖具有最好的粘度。在140°C时,溶液粘度为19.74mPa·s,保留率可达118.27%。长期稳定性研究结果表明,矿化水平为220mg/L的硬葡聚糖在40天内的溶液粘度为89.54%,而杜坦胶可以稳定10天,粘度保持在90mPa·s。这三种生物聚合物都是高度耐酸和耐碱的,在pH3~10范围内粘度变化小于15%。流变学测试表明,迪优坦胶独特的双螺旋结构和硬葡聚糖的刚性三螺旋结构使它们具有比黄原胶更好的粘弹性。因此,这两种生物聚合物,Diutan口香糖,和scleroglucan,具有极端油藏驱油应用的潜力。建议在高达90°C的储层中使用diutan胶进行驱油,在100°C至140°C的储层中使用硬葡聚糖进行驱油。
    The chemically synthesized polymer polyacrylamide (HPAM) has achieved excellent oil displacement in conventional reservoirs, but its oil displacement is poor in extreme reservoir environments. To develop a biopolymer oil flooding agent suitable for extreme reservoir conditions, the viscosity changes and rheological properties of three biopolymers, diutan gum, xanthan gum, and scleroglucan, were studied under extreme reservoir conditions (high salt, high temperature, strong acid, and alkali), and the effects of temperature, mineralization, pH, and other factors on their viscosities and long-term stability were analyzed and compared. The results show that the three biopolymers had the best viscosity-increasing ability at temperatures of 90 °C and below. The viscosity of the three biopolymers was 80.94 mPa·s, 11.57 mPa·s, and 59.83 mPa·s, respectively, when the concentration was 1500 mg/L and the salinity 220 g/L. At the shear rate of 250 s-1, 100 °C~140 °C, scleroglucan had the best viscosification. At 140 °C, the solution viscosity was 19.74 mPa·s, and the retention rate could reach 118.27%. The results of the long-term stability study showed that the solution viscosity of scleroglucan with a mineralization level of 220 mg/L was 89.54% viscosity retention in 40 days, and the diutan gum could be stabilized for 10 days, with the viscosity maintained at 90 mPa·s. All three biopolymers were highly acid- and alkali-resistant, with viscosity variations of less than 15% in the pH3~10 range. Rheological tests showed that the unique double-helix structure of diutan gum and the rigid triple-helix structure of scleroglucan caused them to have better viscoelastic properties than xanthan gum. Therefore, these two biopolymers, diutan gum, and scleroglucan, have the potential for extreme reservoir oil displacement applications. It is recommended to use diutan gum for oil displacement in reservoirs up to 90 °C and scleroglucan for oil displacement in reservoirs between 100 °C and 140 °C.
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  • 文章类型: Journal Article
    天然聚合物基粘合剂是绿色替代品,必须减少受合成粘合剂影响的问题。淀粉和明胶在合成生物基粘合剂方面具有非凡的潜力。柠檬酸(CA),一种天然酸,诱导明胶和淀粉的交联和水解。在这个意义上,这项工作涉及使用明胶胶囊残留物作为一种有前途的材料,以生产生物基粘合剂与木薯淀粉在不同CA浓度的存在下表征其机械,物理化学和微观结构性质。根据CA浓度,可以获得调整到不同应用的制剂,例如液体和压敏粘合剂膜。CA的包含使我们不仅可以改善系统的适用性,因为它可以改变粘合剂的流动性,如观察到的粘度变化(对于具有20%和80%CA的配方,从158.3到90.3,分别)。此外,机械轮廓表明,包含CA增加了粘合剂的粘合强度(对于具有20%和80%CA的配方,从2230.7增加到2638.7,分别)。ATR-FTIR分析强调了CA在粘合剂配方中诱导的结构修饰。
    Natural polymer-based adhesives are green alternatives, necessary to reduce the problems impacted by synthetic adhesives. Starch and gelatin have extraordinary potential for the synthesis of biobased adhesives. Citric acid (CA), a natural acid, induces the crosslinking and hydrolyzing of both gelatin and starch. In this sense, this work deals with the use of gelatin capsule residues as a promising material to produce biobased adhesives in combination with cassava starch in the presence of different CA concentrations characterizing their mechanical, physicochemical and microstructural properties. Depending on CA concentration, formulations adjusted to different applications can be obtained such as liquid and pressure-sensitive adhesive films. The inclusion of CA allows us not only to improve the applicability of the system since it modifies the flowability of the adhesives as evidenced by the observed changes in the viscosity (from 158.3 to 90.3 for formulations with 20 and 80% CA, respectively). In addition, mechanical profiles showed that the inclusion of CA increased the adhesive bond strength (from 2230.7 to 2638.7 for formulations with 20 and 80% CA, respectively). Structural modifications induced by CA in adhesive formulations were highlighted by ATR-FTIR analysis.
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