头孢曲松钠囊泡的研制

以司盘(Span)和胆固醇(CHOL)为膜材,用超声法制备了头孢曲松钠囊泡,通过透射电镜考查其形态和构造,并研究了其在模拟胃液和模拟肠液中的释放情况。实验表明,Span 40与CHOL用量比为5∶3时形成的囊泡,对0.60 mg/mL的注射用头孢曲松钠的包封率可达60%以上,在模拟胃液和模拟肠液中均有缓释作用。     

载5-氟尿嘧啶改性凹凸棒石的制备及缓释性能研究

以酸化凹凸棒石与三甲氧基[3-(苯氨基)丙基]硅烷为原料,采用硅烷化方式制备硅烷化凹凸棒石改性材料,并通过扫描电镜(SEM)、X射线衍射仪(XRD)等技术手段对上述材料及负载5-氟尿嘧啶改性凹凸棒石进行结构表征.研究了载5-氟尿嘧啶改性凹凸棒石在模拟胃液和肠液中的缓释性能,结果表明:在模拟胃液中的释放率为7.35％,模...     

一种淀粉基互穿网络型缓释肥包膜材料的制备及性能研究

采用水溶液聚合法,以甲醛为交联剂,通过淀粉与甘油、100-37H型聚乙烯醇(PVA)多元共聚、交联,制备了一种生物降解性好的互穿网络型缓释肥包膜材料。结果显示,淀粉、甘油、甲醛和PVA的最佳质量分数比率为:20∶4.5∶6.0∶12;包膜材料所制缓释尿素缓释周期达60～80 d,符合GB/T23348—2009规定的缓释效果,其释放机制可能为溶胀-扩散释放机理。     

羟丙基壳聚糖包覆胰岛素微球的性能研究

以壳聚糖和环氧丙烷为原料合成了羟丙基壳聚糖,并以此为壳材,以胰岛素为芯材,制备了平均粒径为13．34μm的微球,并考察了微球的各种性能。通过红外光谱表征了羟丙基壳聚糖和微球的化学结构;热重分析考察了羟丙基壳聚糖微球和包覆胰岛素后微球的热稳定性;采用光学显微镜和扫描电镜观察了不同液体中微球和干品微球的形貌;采用紫外分光光度计绘制胰岛素标准曲线和测定微球的包埋率;并对微球室温下、模拟胃液和模拟肠液中进行了微球稳定性考察。所制备的微球表面光滑、致密、平均粒径适中,且分布较窄,收率和包埋率较高,室温下稳定。根据稳定性考察得出,微球有缓释的功效。     

石蜡包覆微量元素在缓释性饲料中的应用

为了提高饲料中微量元素的利用率,降低环境污染,以石蜡、硬脂酸、单硬脂酸甘油酯为黏合剂,以醋酸钠和磷酸氢钙为填充剂制备出了一系列缓释微丸。并将其在模拟胃液与肠液中进行释放,通过紫外可见分光光度计(UV)测定缓释体系中CuSO₄的浓度,并计算缓释8 h后CuSO₄的累积释放量。探究黏合剂用量、填充剂用量以及微丸粒径对累积释放量的影响。结果表明,石蜡阻滞能力大于单硬脂酸甘油酯大于硬脂酸,填充剂醋酸钠的加入效果优于磷酸氢钙,缓释微丸粒径大小对累积释放量影响不大,填充剂的加入量越大,累积释放量也越大。当石蜡∶醋酸钠∶硫酸铜=0.5∶1∶1时,硫酸铜在模拟胃液与肠液中的累积释放量可达到85.21%。     

壳聚糖/淀粉共混膜的制备及掺杂螺吡喃膜的光致变色性能

以壳聚糖和土豆淀粉为原料,采用溶液共混与流延成膜工艺,制备了壳聚糖/淀粉共混薄膜,探讨了共混薄膜的最佳制备条件,并研究了掺杂螺吡喃的壳聚糖/淀粉共混薄膜的光学性能。结果表明:当壳聚糖与淀粉质量比为1∶1,乙二醛用量为2.0 g,甘油用量为2.0 mL,温度为65℃时,制备的壳聚糖/淀粉共混薄膜性能最佳;添加螺吡喃的壳聚糖/淀粉共混薄膜具有光致变色现象,且随着紫外光照射时间的延长,颜色加深。     

壳聚糖/果胶聚电解质配合物的制备及其性能研究

用天然多糖壳聚糖和果胶合成壳聚糖 /果胶聚电解质配合物 ( PEC) ,探讨了 PEC合成过程反应机理 ,考察 PEC薄膜在水溶液中的溶胀行为、对 p H刺激响应性和做药物释放载体的可能性。关键词 :壳聚糖 ;果胶 ;聚电解质配合物用天然多糖壳聚糖和果胶合成壳聚糖 /果胶聚电解质配合物 ( PEC) ,探讨了 PEC合成过程反应机理 ,考察 PEC薄膜在水溶液中的溶胀行为、对 p H刺激响应性和做药物释放载体的可能性     

O-季铵化改性壳聚糖固载环糊精的制备及其载药性能

对壳聚糖进行O-季铵化改性,并与羧甲基-β-环糊精在均相条件下进行缩合反应,制得O-季铵化壳聚糖固载环糊精(QCSCD),用FTIR、EA和SEM对产物进行表征。以酮洛芬为模型药物,研究其载药及药物释放行为。结果表明,季铵盐基团的引入提高了QCSCD的载药量,为3.97mg/mg,并且改变了QCSCD的pH响应性能。与壳聚糖固载环糊精相反,QCSCD在模拟胃液中的释放速率很快,而在模拟肠液中具有缓释性能。     

阿司匹林壳聚糖-明胶载药微胶囊的制备及性能研究

以阿司匹林为囊芯,壳聚糖和明胶为壁材,采用乳化交联法制备了明胶-壳聚糖微胶囊,考察了芯壁比、水油体积比、乳化剂用量、交联时间等因素对微胶囊性能的影响.采用高效液相色谱法来测定微胶囊的载药量、包封率和释放性能.研究发现,当芯壁比为1∶1,水油体积比为1∶3,乳化剂Span-80用量为5％,交联时间为2h的条件下制备的微胶囊形状规整,载药量为47.99％,包封率为83.18％,且在人工肠液中具有明显的缓释效果.     

pH响应性的虾青素壳聚糖微球制备及应用

以氯乙酸和壳聚糖为原料，通过N,O-羧甲基化化学改性方法制备了水溶性羧甲基壳聚糖，并以此为原料通过乳液法制备羧甲基壳聚糖微球和羧甲基壳聚糖负载虾青素微球。考察了羧甲基壳聚糖微球的形态、分散性和粒径。结果表明，微球最佳制备条件为：羧甲基壳聚糖含量（以水相即去离子水质量为基准，下同）1.0%，油水体积比1∶1，表面活性剂Span 80含量（以油相即液体石蜡体积为基准，下同）4.0%，交联剂戊二醛含量（以油相即液体石蜡体积为基准，下同）7.5%，剪切速率4000 r/min。红外测试表明，微球成功负载虾青素，在虾青素初始添加量为20mg的载药率和包封率分别为10.74%和67.24%。在模拟胃液和模拟肠液中，负载虾青素微球的释放率分别为10%和85%。羧甲基壳聚糖可以用作药物载体。     

Effect of oxidation level on the dual modification of banana starch: The mechanical and barrier properties of its films

Banana starch was oxidized at three different levels and then acetylated. The double‐modified starch was used for film preparation. The physical, mechanical, and barrier properties were tested. The oxidation level increased the whiteness of the film, and the second modification (acetylation) did not affect this parameter. The solubility increased with temperature and oxidation level. However, acetylation decreased the solubility value. At the longest storage times, the solubility decreased because of starch reorganization inside the polymeric matrix. In general, oxidation increased the tensile strength of the films, and a slight increase was observed when the oxidized starch was acetylated. This effect was more noticeable at the longest storage time. The oxidation level decreased the percentage elongation at break, and a slight effect due to acetylation was observed. The film of oxidized–acetylated starch showed a higher elastic modulus value than its oxidized counterpart. The water vapor permeability increased with oxidation level, but the acetylation decreased this parameter. The oxidation increased the hydrophilic character of the starch because of the formation of carbonyl and carboxyl groups that showed more affinity for water molecules. When the oxidized banana starch was acetylated, a decrease in the water vapor permeability was found because the acetylation increased the hydrophobic character of the starch due to the ester group. Films prepared with the double‐modified banana starch had some improved physical, mechanical, and barrier properties, and they may be used in specific applications. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Production and characterization of starch-based films reinforced by ramie nanofibers (Boehmeria nivea)

In this study, the use of cellulose nanofibers from ramie, a plant species with important characteristics of reinforcement, was investigated in the production of bio-based polymer films. A central composite rotatable design was applied to produce the films, analyze the effects of cassava starch, glycerol, and nanofibers content on their properties, obtain mathematical models, response surface plots, and determine an optimum composition. The films produced were characterized by mechanical properties, water vapor permeability (WVP), solubility, and opacity. Microstructure and thermal behavior were also evaluated. The ramie nanofibers content had a positive effect on mechanical and barrier properties, as it increased tensile strength by 207.9%, and decreased WVP and solubility by 52.9 and 72.9%, respectively. Furthermore, the obtained films exhibited homogeneous and cohesive structures, which encourages the use of ramie nanofibers as a reinforcement material in the production of green plastics. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47919.     

豌豆淀粉/聚乳酸双层膜的制备与性能表征

采用溶液流延法以豌豆淀粉（PS）和聚乳酸（PLA）为原料制备了豌豆淀粉/聚乳酸（PS/PLA）双层薄膜。通过对双层薄膜的吸水性、溶解性、水蒸气透过性、拉伸性能、表面形貌等进行测试,研究了薄膜的力学性能、疏水性能以及水蒸气阻隔性能。结果表明：随着双层膜中聚乳酸层的比例增加,双层薄膜的吸水性、溶解性和水蒸气透过性逐渐降低,拉伸强度和拉伸模量逐渐增加,断裂伸长率逐渐下降,表明水蒸气阻隔效果明显,增加了膜的韧性,降低了膜的强度。当PLA和PS的质量比为50：50时,PS/PLA双层膜的拉伸强度为（13.47±0.75）MPa,拉伸模量为（0.848±0.002）GPa;断裂伸长率为（16.11±0.16）%,水蒸气透过系数为0.27×10^-10 g·cm/（cm²·s·Pa）。     

聚乙烯醇/淀粉纳米晶复合膜的制备及表征

利用蜡质玉米淀粉通过硫酸酸解制备淀粉纳米晶（SN）,并采用溶液流延法制备聚乙烯醇（PVA）/SN复合膜,研究SN对复合膜结构和性能的影响。结果表明,制备的SN样品为盘状颗粒,平均直径为30～60 nm;随着SN含量的增加,PVA/SN复合膜的力学性能和阻隔性能均呈现先增后减的变化;在SN含量为10 %时,复合膜的拉伸和阻隔性能最好,拉伸强度由纯PVA膜的47 MPa提高至54 MPa,气体透过系数相对于纯PVA膜也降低了70 %。     

淀粉微晶/聚乙烯醇复合薄膜的制备与性能

在制备淀粉微晶的基础上,将淀粉微晶与聚乙烯醇共混制备复合材料薄膜,讨论了原料配比、混合温度、混合时间和转速等因素对复合薄膜性能的影响。正交实验的结果表明:当聚乙烯醇与淀粉微晶的质量配比为1∶4,混合温度为90℃,混合30min时制得的复合薄膜的性能最好。     

淀粉纳米晶对天然胶乳性能的影响

将淀粉纳米晶作为天然胶乳的补强剂,研究其对天然胶乳的胶体性能及硫化胶膜的物机性能、耐水性和耐溶剂的影响。研究结果表明:将淀粉纳米晶加入天然胶乳后,胶乳的粘度变化不大,机械稳定度提高;硫化胶膜的物机性能明显提高,耐溶剂性提高,而耐水性降低。     

Composition optimization of polyvinyl alcohol/rice starch/silk fibroin‐blended films for improving its eco‐friendly packaging properties

Biopolymers obtained from renewable sources have been exploited in developing biomaterials with eco‐friendly properties. Most biopolymers have some limitations because of their poor mechanical properties, high water solubility, or low transparencies. In this study, some biopolymers, that is, silk fibroin (SF) and rice starch (RS) were used as starting materials together with polyvinyl alcohol (PVA) as a film‐former for preparing novel eco‐friendly films. The film preparations were done by solution casting with two different sequences of blending and the film compositions were optimized. Results from UV, SEM, and film properties testing on mechanical properties, degree of swelling, water solubility, and also oxygen permeability indicated that all film properties depended on their compositions and order of blending. The PVA/RS film obtained is transparent with good mechanical properties and low water solubility. The addition of SF increases the permeability of oxygen and also the degradability of the films. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Mechanical and Physical Properties of Cassava Starch-Gelatin Composite Films

The effect of gelatin concentrations on the mechanical properties and solubility of cassava starch-based films containing glycerol was studied. Increasing concentration of gelatin increased tensile strength but reduced elongation at break and water solubility of the composite films. Films containing 30% gelatin showed the highest tensile strength. Fourier transform infrared spectroscopy (FT-IR) spectra indicated intermolecular interactions between cassava starch and gelatin in composite films. The X-ray diffraction (XRD) technique demonstrated pseudo-crystalline regions in the cassava starch-gelatin composite films, and it is supposed that the interactions between cassava starch and gelatin were shown in the diffractograms by shifts in scattering angles. The differential scanning calorimetry (DSC) thermograms and scanning electron microscopy (SEM) micrographs confirmed homogeneity of cassava starch-gelatin films. Cassava starch-gelatin composite films have the potential to replace conventional packaging, and the films developed in this work are suggested to be suitable for low-moisture food and pharmaceutical products.     

Effects of plasticizer/cross-linker on the mechanical and thermal properties of starch/PVA blends

Biodegradable blends of potato starch and polyvinyl alcohol were prepared by solution casting method. Citric acid was employed to introduce the plasticizing effect into the starch materials. Glutaraldehyde as cross-linker was used to enhance the properties of the blend films. Cross-linking is a common method to improve the strength and stability of starch products. The effects of citric acid and glutaraldehyde on the mechanical properties, thermal properties and swelling degree were investigated. The prepared films were measured for their antibacterial activities and biodegradability. The blend samples were characterized by the thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and FTIR analysis techniques. From the mechanical properties study, it was analyzed that the blend films showed improvement in their tensile strength after cross-linking with glutaraldehyde. The SEM micrographs indicated that the blend films were smooth without any cracks, pores and were well cross-linked. The TGA curves showed that there was an increase in the thermal stability of the blend films after cross-linking as compared to uncross-linked blend films. The prepared films showed good antibacterial properties against Gam-positive and Gram-negative bacteria. The biodegradability of the blends was determined by placing the samples in compost soil for different time intervals and were found to be biodegradable in nature.     

Effect of blend composition and structure on biodegradation of starch/ecoflex‐filled polyethylene films

A method to blend starches and polyethylene, and thus improve the environmental footprint, was investigated. Unlike traditional methods that utilize compatibilizers or rely on reactive extrusion to achieve the desired material compatibility, a high amylose starch, such as Gelose 80, was mixed with native starch, converted to thermoplastic starch, and compounded with Ecoflex and polyethylene. Films showed good integrity and were evaluated for mechanical properties, anaerobic biodegradability, and structure changes both before and after anaerobic sludge digestion. Mechanical properties were sufficient that these films might be utilized in a number of applications but were not recommended as a sustainable solution. Biodegradation was below the theoretical maximum, was not a linear function of the amount of biodegradable materials incorporated in the films, and was depressed further as the proportion of polyethylene increased due to an encapsulation effect. Structural evaluation showed the components of the blends remained as separate phases and the structure of the Gelose 80 was reminiscent of interphase material. Biodegradation yield appeared to be principally driven by connectivity of the starches within the films to the anaerobic sludge digestion environment. Recommendations for additional studies were given. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011