正交设计法优化黄柏涂膜剂成膜材料的制备工艺

采用L9(33)正交实验,以涂膜剂外观性状及成膜时间为考核指标,对黄柏涂膜剂成膜材料的制备工艺进行了优化.结果表明,在10％ PVA-124用量为10 mL、10％ PVA-1788用量为10 mL、甘油用量为1.5 mL的条件下得到的成膜材料成膜性好、易于涂展、韧性强,黄柏提取物在其中溶解均匀.     

有无混合器对圆形直管内空气传热膜系数α影响的研究

研究了空气分别在有无混合器的圆形直管内湍流流动时的传热膜系数α,比较了两种情况下α及准数关联式的差异。结果表明:在相同条件下,空气在有混合器的强化传热管中其α远高于无混合器的圆形直管;且空气在强化管内湍流时的α其准数关联式不同于圆形直管。     

聚苯胺/顺丁橡胶导电复合膜的制备及性能研究

采用两种方法实现顺丁橡胶和掺杂态聚苯胺的复合,即溶液法和机械共混法,并对这两种方法制备的复合样品的性能进行了分析研究。结果表明,溶液法比机械共混法制备的样品性能好。聚苯胺/顺丁橡胶导电复合膜的电导率,随着掺杂态聚苯胺含量的增加而增大。     

一种新型抗菌白炭黑的研究

以竹醋液和硫酸的混酸为酸化剂、采用沉淀法合成抗菌白炭黑,考察了反应温度、混酸配比、聚乙二醇添加量、水玻璃浓度和打底水量对白炭黑吸油值的影响。正交实验结果分析表明,温度、打底水量、聚乙二醇添加量对吸油值影响极为显著,混酸配比影响较为显著,水玻璃浓度不显著。实验验证产品比表面积和吸油值高,具有良好的抗菌效果。     

脱胶工艺对竹纤维抑菌性能的影响

采用简单工艺法和预氧处理一氧法,对竹进行脱胶制得竹纤维,再选取了吸收法对制取的纤维进行抑菌性能测试,通过计算抑菌率来评价其抑菌效果.试验表明:在其他条件相同的情况下,采用的脱胶工艺越复杂,使用的化学试剂越多,竹纤维的抑菌性能就越小.     

亲水性无定型TiO_2/SiO_2薄膜及其强化传热性能研究

采用溶胶-凝胶技术在传热管表面涂覆TiO2/SiO2复合溶胶涂层,并通过优化热处理温度和干湿交替处理工艺,提升涂层的亲水性能和强化传热性能。试验结果显示,在热处理温度为200℃时,凝胶涂层以无定型结构为主;热处理试样经过6次干湿交替处理后,即可使表面接触角降低到10°左右;传热管表面较好的润湿性能,可显著提升降膜式换热器的换热效率。     

Microporous network‐assisted formation of copper‐in‐polymer gradient composite film

In this article, a copper‐in‐polymer‐gradient composite film (CPGCF) was synthesized by electrochemical strategy via reducing a solvent‐swollen cathode film (SCF). The latex nanoparticles of a ternary copolymer including styrene, butyl acrylate, and acrylic acid structural units play the key role to form well‐graded copper distribution in this ternary copolymer matrix through the porous morphological structure developed by latex nanoparticle semimelt joining. The morphological structure along cross‐section of CPGCF includes three layers: (1) a dense copper layer in ternary copolymer matrix whose most outside was originally attached to cathode in electrochemical reactor, (2) a shrublike layer that grew from dense copper layer, and (3) a clear layer in which there is no obvious reduced copper phase whose most outside was originally contacted with liquid electrolyte medium in electrochemical reactor. As experimental aspects, the influences of emulsion polymerization conditions of ternary copolymer, predrying time and temperature of SCF, dc voltage in electrochemical reduction on CPGCF structure were investigated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Coumarin‐based polymer and its silver nanocomposite as advanced antibacterial agents: Synthetic path,kinetics of polymerization,and applications

A novel polymer bearing coumarin pendants of 4‐allyloxy‐2H‐chromen‐2‐one (ACO) was synthesized by atom transfer radical polymerization (ATRP) in toluene at 110°C using 2‐Bromoisobutyryl bromide (BIBB), Cu (I) Br, and 2,2′‐bipyridyl (bpy) as initiator, catalyst, and ligand, respectively. The most appropriate molar concentration ratio of [ACO] : [BIBB] : [Cu (I) Br] : [bpy] was found to be 40 : 1 : 1 : 2 for controlled polymerization. Successful chain extension polymerization of poly (4‐allyloxy‐2H‐chromen‐2‐one) (PACO) confirms the livingness of the process. The activation energy (E_a) (76.26 kJ mol^?1) and enthalpy of activation (ΔH^?) (73.07 kJ mol^?1) were in good agreement to each other proving the feasibility of the reaction and negative value of entropy of activation (ΔS^?) (?320 J mol^?1 K^?1) supported the highly restricted movement of reacting species in transition state during polymerization. Initial polymer decomposition temperature of PACO was found to be 130°C. SEM analysis revealed that polymer surface is not smooth with pointed rod like shapes. The polymer/Ag nanocomposite was synthesized and examined in view of antibacterial effect against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Proteus mirabilis, and Klebsiella pneumonae. PACO and its Ag nanocomposite (PACON) have been found to be active selectively against bacterial pathogen E. fecalis with minimum inhibitory concentration of 50 and 32 μg mL^?1, respectively. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Absorption and reflection of infrared radiation by polymers in fire‐like environments

In large‐scale fires, the input of energy to burning materials occurs predominantly by radiative transfer. The in‐depth (rather than just surface) absorption of radiant energy by a polymer influences its ignition time and burning rate. The present investigation examines two methods for obtaining the absorption coefficient of polymers for infrared radiation from high‐temperature sources: a broadband method and a spectral method. Data on the total average broadband transmittance for 11 thermoplastics are presented (as are reflectance data), and the absorption coefficient is found to vary with thickness. Implications for modeling of mass loss experiments are discussed. Copyright © 2011 John Wiley & Sons, Ltd.     

Thermal and mechanical behavior of natural rubber latex‐silica aerogel film

A major problem in most natural rubber latex (NRL) commonly encountered like other polymer is susceptibility to mechanical properties and thermal degradation; particularly in thin film due to the presence of double bonds in the main chain. Therefore, it is desirable to seek for ways of improving these properties. Silica aerogel is a material with extraordinary properties was believed to have potential enhance properties in NRL films because of its high specific surface area. Therefore, based on the unique character of silica aerogel, NRL‐silica aerogel film was developed by latex compounding and dry coagulant dipping to form thin film where silica aerogel acts as filler. Silica aerogel, synthesized from rice husk was dispersed in a ball‐mill using distilled water for NRL compounding. Results indicate that increasing silica aerogel loading enhances the mechanical properties of the NRL‐silica aerogel film. Effects of postvulcanization processes were also investigated, whereby the best reinforcing effect was obtained at 4 phr silica aerogel loading with leaching postvulcanization condition. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012