Influence of Codiluent Reactives in Electron Beam Cured Films

Two urethane diacrylates—one aromatic, M1100; and the other aliphatic, M1200—have been used to prepare elastic films under electron beam (EB) irradiation. Two monofunctional diluents are used; N-vinyl pyrrolidone (NVP) is used as the reactive diluent monomer, and the second one, called the codiluent, is chosen from a series of acrylated monomers with T_g values lower than that of NVP. Pencil hardness; gel content; swelling ratio in acetone; and mechanical properties such as yield strength, break strength, elongation, and Young's modulus of the cured films are determined. Among the various codiluents used, vinyl acetate (VAc), cyclohexyl acrylate (CHA), and tertiary butyl acrylate (t-BA) played a significant role in inducing improved Theological properties in the cured films.     

拉伸倍率对BOPP薄膜性能的影响

选取一种双向拉伸聚丙烯（BOPP）薄膜专用料进行了双向拉伸实验,在不同拉伸倍率下制备了BOPP薄膜试样,并对原料性能及所制备薄膜的光学性能、力学性能等进行了研究,从而建立起了拉伸倍率与薄膜拉伸成型和薄膜性能间的对应关系。结果表明,随纵向（MD）拉伸倍率的增大,薄膜雾度降低,光泽度升高;而随横向（TD）拉伸倍率的增大,薄膜的TD向拉伸强度呈线性提高,BOPP薄膜的性能主要受TD向拉伸倍率的影响。     

Codiluent effect on the properties of UV-cured films

Different formulations were developed with an urethane oligomer combined with a number of reactive diluents with different functionalities such as N-vinylpyrrolidone (monofunctional), butanediol diacrylate (difunctional), tripropylene glycol diacrylate (difunctional), and trimethylolpropane triacrylate (trifunctional). The films were prepared with these formulations and cured under UV radiation in the presence of the photoinitiator Irgacura 184. Their properties were characterized. The effect of codiluents of low glass transition temperatures like ethyl hexyl acrylate and methoxyethyl acrylate on the properties of these films was studied. These formulations were then applied as thin coatings on the leather surface in order to study the improvement of the leather substrate. Both tensile strength and elongation of the treated leather increased. The gloss of the coated leather was also enhanced. Incorporation of a plasticizer into these systems substantially improved the rheological properties of the coated leather. © 1995 John Wiley & Sons, Inc.     

Influence of Amphiphilic Plasticizer on Properties of Thermoplastic Starch Films

Thermoplastic starch powders and films were produced by using different combinations of hydrophilic (malic acid and water) and amphiphilic (isoleucine and butyric acid) plasticizers. Spray drying was used to produce thermoplastic starch powder followed by compression molding for the development of films. In all plasticized formulations, the rate of retrogradation was inhibited until the seventh day. The crystallinity and moisture sensitivity of the freshly prepared films were dependent on amphiphilic plasticizer quantity in formulation. Fourier transform infrared spectroscopy and thermogravimetric analysis showed an effective interaction of starch with isoleucine. Isoleucine formulated films showed the highest tensile strength, whereas malic acid-rich films showed better strain values.     

Influence of Drying Conditions on Physical Properties of Alginate Films

The effect of drying conditions of the film-forming solution on thickness, moisture content, water vapor permeability, and tensile properties of alginate films were investigated. A long period of constant rate was observed in all conditions and the model proposed by Wang and Singh was able to adjust the drying data. As expected, there was a clear effect of temperature on drying kinetics; that is, increasing the drying temperature decreased the drying time. Considerable glycerol losses were observed when alginate gel was oven dried at temperatures above 40°C. Compared to other drying conditions, films oven dried at 60°C were thinner, had lower moisture content, and were less flexible.     

阳离子聚乙烯蜡乳液对树脂涂膜性能的影响

将阳离子聚乙烯(PE)蜡乳液与阳离子树脂混合成膜,考查了蜡乳液对涂膜力学性能、耐水性和耐溶剂性的影响。实验结果表明:当5∶55≤m(PE蜡乳液)∶m(阳离子树脂)≤20∶40时,PE蜡乳液可改善丙烯酸树脂膜和聚氨酯膜的抗张强度和撕裂强度等力学性能,并能提高涂膜的耐磨性、耐水性和耐溶剂性。     

Influence of Substrate Properties on the Dewetting Dynamics of Viscoelastic Polymer Films

We studied the dewetting process of thin polystyrene (PS) films on silicon substrates, coated with a thin, irreversibly adsorbed polydimethylsiloxane (PDMS) layer, by optical microscopy and atomic force microscopy. Besides demonstrating the exceptional potential of dewetting for a sensitive characterization of rheological properties of PS thin films, characterized by a stress-relaxation time, τ₁, we focused on the influence of the frictional behaviour (energy dissipation mechanism) at the interface between the PDMS-coated silicon wafer and the PS film on the dewetting process. Our results show that the initial stages of dewetting depend sensitively on the thickness and the way the PDMS layer was adsorbed. The maximum width of the dewetting rim at τ₁ increased with increasing PDMS layer thickness, which can be interpreted as an increase of the effective, velocity-dependent slippage length. Interestingly, τ₁ was found to be almost independent of the substrate properties. Our results demonstrate that dewetting is a really powerful approach for rheological and frictional studies of thin polymer films.     

Influence of Substrate Properties on the Dewetting Dynamics of Viscoelastic Polymer Films

We studied the dewetting process of thin polystyrene (PS) films on silicon substrates, coated with a thin, irreversibly adsorbed polydimethylsiloxane (PDMS) layer, by optical microscopy and atomic force microscopy. Besides demonstrating the exceptional potential of dewetting for a sensitive characterization of rheological properties of PS thin films, characterized by a stress-relaxation time, τ₁, we focused on the influence of the frictional behaviour (energy dissipation mechanism) at the interface between the PDMS-coated silicon wafer and the PS film on the dewetting process. Our results show that the initial stages of dewetting depend sensitively on the thickness and the way the PDMS layer was adsorbed. The maximum width of the dewetting rim at τ₁ increased with increasing PDMS layer thickness, which can be interpreted as an increase of the effective, velocity-dependent slippage length. Interestingly, τ₁ was found to be almost independent of the substrate properties. Our results demonstrate that dewetting is a really powerful approach for rheological and frictional studies of thin polymer films.     

Ultra-Violet Radiation-Cured Biofiber Composites from Kenaf: The Effect of Montmorillonite on the Flexural and Impact Properties

Abstract

Biofiber composites, cured by ultra-violet (UV) radiation were produced using kenaf fibers as the reinforcing agent and unsaturated polyester as the matrix. This research work focused on the effects of the incorporation of kenaf fiber, montmorillonite (MMT), and cetyl trimethyl ammonium bromide-modified MMT (CTAB-MMT) in the unsaturated polyester composite. Overall, the incorporation of kenaf fibers in the form of mat had improved the flexural and impact properties of the composites. Addition of MMT into the kenaf fiber-polyester system showed an improvement up to 1% MMT after which it decreased. The increase was attributed to better stress transfer mechanism in the matrix. However, further increase in the MMT loading had resulted in the decrease in the properties, which was believed to be due to agglomeration. Modification of MMT with CTAB had produced composites with higher flexural and impact properties as compared to those without modification. This was attributed to a combination of effective dispersion of MMT in the matrix, availability of effective high aspect ratio MMT, and enhanced compatibility between CTAB-MMT with the matrix.     

工艺参数对TiO2薄膜性能的影响

研究了基本工艺参数（如聚乙二醇的添加量和分子量、热处理制度、薄膜层数）对溶胶凝胶法制备TiO2薄膜性能的影响。结果表明：添加分子量2000的聚乙二醇1．0g（相对于100ml溶胶）,以2℃/min的速度缓慢升温至550℃,保温1h,制得的TiO2 10层薄膜,表现出分解稀醋酸的光催化活性较好。     

EVA对农膜再生料的力学性能及流变性能的影响

用熔融共混法制备了EVA与农膜再生料（RPE）的共混材料,研究了EVA对农膜再生料的改性作用,并与新料低密度聚乙烯（LDPE）进行了对比研究。对再生料、改性材料和新料进行了力学性能分析、旋转流变分析、转矩流变分析和形貌分析。结果表明,EVA可以显著提高农膜再生料的断裂伸长率,对拉伸强度影响不大,当EVA用量为50%时,改性材料的断裂伸长率和拉伸强度都和新料相当。EVA可以提高再生料的相容性,改善其流变性能和加工性能,使再生料的流变行为接近新料,更容易加工。     

不同工艺对PANI/PAA复合薄膜的电致变色性能影响研究

采用直接聚合法与逐层镀膜法分别成功制备了聚苯胺(PANI)/聚丙烯酸(PAA)复合薄膜,通过扫描电镜(SEM)、傅里叶变换红外光谱(FT-IR)等方法考察了两种工艺制备的薄膜的形貌和微结构,并测定了两种复合薄膜的循环伏安性能(CV)、电流响应特性(CA)及电致变色性能。结果表明,SEM与FT-IR证实了两种方法制备的PANI/PAA复合薄膜仅在材料结构上有所不同;直接聚合法制备的PANI/PAA复合薄膜(PANI/PAA-DP)表面具有较大颗粒,2对明显的氧化还原峰,氧化态和还原态的响应时间分别为120ms和226ms,在600~700nm波长处的透过率调制幅度为10%;逐层镀膜法制备的PANI/PAA复合薄膜(PANI/PAA-LP)具有多孔的网络结构,3对氧化还原峰,氧化还原反应更明显,电致变色性能更优异,其氧化态和还原态的响应时间分别为45ms和67ms,在600~700nm波长处的透过率调制幅度可达40%。     

Influence of Cr Ion Implantation on Physical Properties of CuO Thin Films

Cupric oxide is a semiconductor with applications in sensors, solar cells, and solar thermal absorbers. To improve its properties, the oxide was doped with a metallic element. No studies were previously performed on Cr-doping using the ion implantation technique. The research goal of these studies is to investigate how Cr ion implantation impacts the properties of the oxide thin films. CuO thin films were deposited using magnetron sputtering, and then chromium ions with different energies and doses were implanted. Structural, optical, and vibrational properties of the samples were studied using X-ray diffraction, X-ray reflectivity, infra-red spectroscopy, Raman spectroscopy, and spectrophotometry. The surface morphology and topography were studied with ellipsometry, atomic force microscopy, and scanning electron microscopy. A simulation of the range of ions in the materials was performed. Ion implantation had an impact on the properties of thin films that could be used to tailor the optical properties of the cupric oxide and possibly also its electrical properties. A study considering the influence of ion implantation on electrical properties is proposed as further research on ion-implanted CuO thin films.     

添加剂对纳米晶铜膜微观结构及纳米压痕性能的影响

采用电刷镀技术制备不同晶粒尺寸的纳米晶铜膜。利用透射电子显微镜分析电刷镀纳米晶铜膜的微观结构,计算晶粒尺寸范围;利用UNMT-1型纳米力学综合测试系统对电刷镀纳米晶铜膜进行室温纳米压痕实验。由实验可知,添加剂对纳米晶铜膜的晶粒尺寸和压痕硬度均有较大的影响。在添加剂45g/L条件下,平均晶粒尺寸最小为32nm左右,压痕硬度为3.26GPa;在添加剂1g/L条件下,平均晶粒尺寸增大到150nm左右,压痕硬度减小为1.72GPa。     

柠檬酸改性对变色聚乙烯醇流延膜性能的影响

以聚乙烯醇（PVA）为母液、柠檬酸为交联剂制备了变色PVA流延膜,并对薄膜的力学性能、光学性能和热稳定性进行了研究。结果表明,随着柠檬酸质量分数的增大,薄膜的抗张强度增大,伸长量减小;随着柠檬酸质量分数的增加,薄膜的雾度呈上升趋势;柠檬酸质量分数对变色薄膜的颜色及颜色变化也有较大影响;添加柠檬酸提高了薄膜的热分解温度,从而提高了薄膜的热稳定性。     

不同工艺对PANI/PAA复合薄膜的电致变色性能影响

采用直接聚合法与逐层镀膜法分别成功制备了聚苯胺(PANI)/聚丙烯酸(PAA)复合薄膜,通过SEM、FTIR考察了两种工艺制备的薄膜的形貌和微结构,并测定了两种复合薄膜的循环伏安性能(CV)、电流响应特性(CA)及电致变色性能。结果表明,SEM与FTIR证实了两种方法制备的PANI/PAA复合薄膜仅在材料结构上有所不同;直接聚合法制备的PANI/PAA复合薄膜(PANI/PAA-DP)表面具有较大颗粒,两对明显的氧化还原峰,氧化态和还原态的响应时间分别为120 ms和226 ms,在600～700 nm波长处的透过率调制幅度为10%;逐层镀膜法制备的PANI/PAA复合薄膜(PANI/PAA-LP)具有多孔的网络结构,3对氧化还原峰,氧化还原反应更明显,电致变色性能更优异,其氧化态和还原态的响应时间分别为45 ms和67 ms,在600～700 nm波长处的透过率调制幅度可达40%。     

氢对非晶氮化硅薄膜键合结构和光学吸收特性的影响

采用对靶磁控反应溅射技术以H2和N2为反应气体在不同氢气流量(15~25 Sccm)条件下制备了氢化非晶氮化硅(a-SiN∶H)薄膜,并利用傅立叶红外透射光谱(FTIR)和紫外-可见透射光谱(UV-VIS)对薄膜的键合结构和光学吸收特性进行了分析。结果表明,氢气流量20Sccm时薄膜中氢的键密度最大,薄膜无序度最减小;薄膜的光学带隙Eg和E04逐渐增大。薄膜原子间键合结构和薄膜有序性的变化可归因于反应溅射过程中氢气的钝化和刻蚀作用。     

氧气对磁控溅射HfO2薄膜电学性能的影响

采用射频磁控溅射法在无氧和有氧气氛下制备了HfO2薄膜.通过X射线衍射(XRD)、X射线光电子能谱(XPS)、高分辨透射电子显微镜(HRTEM)、傅立叶变换红外光谱(FTIR)、椭圆偏振光谱(SE)以及电容-电压(C-V)测试对薄膜的结构、成分、HfO2/Si界面和HfO2栅介质MOS结构的电学性能等进行了分析表证.结果表明,溅射过程中通入氧气后,薄膜出现了较明显的结晶化;薄膜的氧化程度得到提高,成分更接近理想化学计量比HfO2.在HfO2/Si界面处存在的SiO2界面层,有氧条件下界面层的厚度增大.氧气的通入改善了HfO2栅介质MOS结构的电学性能.     

热收缩聚酯薄膜性能的研究

对经间苯二甲酸 (IPA)及新戊二醇 (NG)改性的三种热收缩膜专用聚酯性能及其薄膜的热收缩性能进行了研究。结果表明 :与常规 PET相比 ,改性聚酯的结晶和熔融行为有很大不同 ;经 (NG)改性的聚酯薄膜在热空气中的热收缩率超过 35 % ;薄膜在 Tg附近热收缩率变化最大。