菌蚀型功能材料的合成与生物降解

设计与合成一种菌蚀型功能材料,探讨在模拟结肠环境下,材料降解性能与化学结构关系.用对甲基丙烯酰胺偶氮苯(BMAAB)为偶联剂,以偶氮二异丁腈(AIBN)为引发剂,以甲基丙烯酸羟乙酯(HEMA)、甲基丙烯酸甲酯(MMA)、甲基丙烯酸(MAA)为共单体,合成聚甲基丙烯酸羟乙酯-甲基丙烯酸-甲基丙烯酸甲酯[P(HEMA-MAA-MMA)]无规偶氮聚合物.用紫外、红外、核磁共振手段进行化学结构测定.测定该材料溶胀性能,建立体外厌氧条件下模拟结肠环境模型,用GPC凝胶色谱法、DSC差热分析法与SEM 扫描电镜法.比较聚合物降解前后分子量、热性能与形态变化.试验结果表明, 材料溶胀指数Q随材料中HEMA-MAA含量增加而增大.材料在模拟结构内容液环境中,降解程度与材料中亲水组分含量直接相关.该材料具有菌蚀功能,有望作为结肠靶向给药系统载体.     

PHPMA/SiO2有机无机杂化材料的研究

以甲基丙烯酸p羟丙酯(HPMA)、正硅酸乙酯(TEOS)为原料，基于溶胶凝胶技术合成出聚甲基丙烯酸B羟丙酯PHPMA／SiO2均质透明有机无机杂化材料。采用气相色谱(GC)技术、紫外可见分光度技术研究TEOS与HPMA杂化机理。利用FT—IR和DSC技术对杂化材料进行表征。实验结果表明，HP—MA的活性羟基与TEOS的乙氧基间能够发生杂化反应，形成以Si—O--C链结合的有机无机杂化网络，这些有机无机杂化网络赋予了材料优异的力学性能和热学性能。根据实验结果预测了PHPMA／SiO2杂化材料网络模型。     

甲基丙烯酸与木薯淀粉接技共聚反应研究

以硝酸铈铵为引发剂，以南方地区特有的木薯淀粉与部分中和的甲基丙烯酸接枝共聚。研究了单体转化率、淀粉接枝率和接枝效率与甲基丙烯酸浓度、引发剂浓度、反应温度和时间、甲基丙烯酸中和度之间的关系。实验结果表明，单体浓度为１．５ｍｏｌ／Ｌ，引发剂浓度为１．０ｍｍｏｌ／Ｌ反应温度为５０℃，反应时间２ｈ，中和度＞８０％时，单体转化率和接枝率较高，单体中和度对接枝反应影响显著。     

PLA嵌段的聚氨酯丙烯酸酯大单体的合成及聚合物的制备

利用乳酸与1,4-丁二醇(BDO)的缩聚反应,合成了PLA-BDO-PLA型嵌段预聚物,该预聚物与异佛尔酮-二异氰酸酯(IPDI)、甲基丙烯酸β羟乙酯(HEMA)反应,得到了聚氨酯丙烯酸酯大分子单体,将其固化制得聚氨酯材料.对材料的热行为(TG、DTG)及降解性能进行了表征,结果表明,该聚氨酯材料具有较好的热稳定性和降解性,在70 ℃水中静置24 h,其降解率可达9.55%;在室内环境下放置120 d后,材料的冲击强度下降26.3%.     

甲基丙烯酸与木薯淀粉接枝共聚反应研究

以硝酸铈铵为引发剂，以南方地区特有的木薯的淀粉与部分中的和甲基丙烯酸接枝共聚。研究了单体转化率，淀粉接枝率和接枝效率与甲基丙烯酸浓度。引发剂浓度，反应温度和时间，甲基丙烯酸中和度之间的关系。     

甲基丙烯酸马来海松环氧树脂/聚氨酯丙烯酸酯/碳纳米管复合材料的制备和性能

为了保护环境和利用可再生资源,文中合成了甲基丙烯酸马来海松酸环氧树脂(MREMA)和聚氨酯丙烯酸酯(PUA),将MREMA和PUA按质量比1∶1进行UV固化反应,并用羟基多壁碳纳米管(HCNTs)改性制备纳米复合材料。利用红外光谱仪、热重分析仪、动态力学谱仪和漆膜测试仪等研究了碳纳米管对MREMA/PUA材料的热性能、动态力学性能以及涂膜性能的影响。结果表明,加入HCNTs可以明显改善材料的热性能和动态力学性能。加入0.5%HCNTs,材料的玻璃转化温度Tg达到173.4℃,与纯组分相比提高了64.6℃;加入0.7%HCNTs,材料的起始热分解温度提高了38.2℃。UV-光固化涂膜的硬度也因加入HCNTs而提高,且涂膜具有很好的物理化学性能。     

甲基丙烯酸正丁酯／甲基丙烯酸羟乙酯共聚树脂研究

采用悬浮聚合法合成了甲基丙烯酸正丁酯、甲基丙烯酸β羟乙酯二元共聚树脂，采用冻胶纺丝技术制备了纤维状共聚物树脂，研究了甲基丙烯酸β羟乙酯含量对树脂饱和吸油率、吸油速率以及充分溶胀后树脂剩余率的影响，分别利用傅立叶变换红外光谱（FTIR）和动态热机械分析仪（DMA）对树脂的化学结构和动态力学性能进行了分析和讨论，利用软件materials studio对甲基丙烯酸正丁酯、甲基丙烯酸β羟乙酯共聚过程中的物理缠结能力进行了模拟预测。     

含香豆素功能基聚合物的合成及荧光性能

以邻羟基苯甲醛、邻氨基巯酚、丙二腈为原料合成了有机光致发光材料6-氯甲基-3-(2-苯并噻唑基)-香豆素,将这种新型香豆素与甲基丙烯酸甲酯(MMA)、甲基丙烯酸二甲胺基乙酯(DM)的共聚物(CPA)进行季铵化反应,制得侧基上带有不同配比香豆素的新型发光高分子化合物(C-CPA)。通过差示扫描量热法(DSC)、凝胶色谱法(GPC)、FT-IR和UV-Vis证明了接枝反应是成功的。同时研究发现接枝香豆素的高分子化合物具有很好的荧光性能,这为合成具有优异发光性能的接枝型高分子功能材料提供了一条新的途径。     

含可加成反应偶氮苯聚合物的制备及表征

经过Diels-Alder反应等步骤制备了新型马来酰亚胺单体——甲基丙烯酸-4-(呋喃-马来酰亚胺乙基)酯(MMA-FMI),经过重氮、偶合等步骤制备了新型含呋喃环的偶氮苯单体——甲基丙烯酸-4-(4-呋喃-2-甲基-2-乙酸酯基偶氮)苯酯(MMA-FAzo),MMA-FMI、MMA-FAzo再与甲基丙烯酸-4-(4-甲氧基偶氮)苯酯(MMA-Azo-OCH_3)无规共聚得到含可加成反应偶氮苯聚合物(PAzo)。采用核磁共振氢谱、傅里叶变换红外光谱、凝胶渗透色谱对聚合物结构进行表征;使用紫外-可见分光光度计研究聚合物的顺反异构化行为,发现聚合物的光致顺反异构化速率常数为0.217 s~(-1),聚合物PAzo具有快速光响应性能;通过热失重分析仪研究聚合物的可加成特性;通过热可逆实验证明,交联的聚合物仍具有可回收与再加工性。     

丙烯酰胺-甲基丙烯酸共聚物的NMR研究

用FT-IR光谱,1H-NMR谱,质子弛豫时间等方法研究了在热引发条件下甲基丙烯酸和丙烯酰胺的共聚合反应,讨论了甲基丙烯酸(MAA)、丙烯酰胺(AM)在不同配比,不同反应时间下的共聚合转化率,以及单体配比与聚合物链运动的关系。结果表明,随着甲基丙烯酸(MAA)含量增大,共聚合转化率呈先增大后减小趋势。当AM与MAA物质的量之比为2∶1,热引发共聚合反应时间为3 h,共聚合转化率可达90.2%。从自旋-晶格弛豫时间(T1)和自旋-自旋弛豫时间(T2)的测定得出,当单体配比中MAA含量增加,大分子运动的相关时间(τ)变长,大分子中质子的平均间距变小,链段运动变慢,而高频短程运动则变化不明显。     

The optical properties of CuGa0.5In0.5Se2 thin films

CuGa_0.5In_0.5Se₂ thin films with thickness in the range 50 to 280 nm were deposited by thermal evaporation of prereacted material on glass substrates. The films were found to be polycrystalline with single phase having chalcopyrite structure as that of bulk material. The optical constants of these films were determined by transmittance and reflectance measurements at normal incidence for light in the wavelength range 400 to 1200 nm. Three characteristic energy gaps of 1.30, 1.55 and 2.46 eV were obtained from an analysis of the optical absorption spectrum. The optical constants of the films appear to be independent of the substrate temperature.     

Growth and characterization of an organic nonlinear optical crystal: Glycinium trichloroacetate

Single crystal of glycinium trichloroacetate, an organic nonlinear optic (NLO) material, has been grown by slow solvent evaporation technique at room temperature. The grown crystal was subjected to single crystal X-ray diffraction for confirming the coordination formed, and the presence of various functional groups was studied by FTIR in the range 4000–450 cm⁻¹. UV–Visible transmittance studies were performed to analyze optical transparency of the crystal and second harmonic generation was investigated to explore the NLO property of the material. Thermogravimetric and differential thermal analysis have been performed to study thermal properties of the grown crystal. Dielectric constant and dielectric loss were studied at different temperatures and frequencies. Vicker's microhardness testing was carried out on the as grown crystal to reveal the mechanical properties of the crystal. Etching studies were made on the as grown crystal to analyze the structural imperfection of the crystal.     

Transmittance of a thin Saran film in the 45-584-Å wavelength region

The transmittance of a free-standing Saran film, 4260 ? thick, has been measured by means of synchrotron radiation in the 45-584-? wavelength region. The transmittance was calculated by means of the elemental composition of the film material as determined by x-ray photoelectron spectroscopy and the optical constants as derived from atomic-scattering factors. The calculated transmittance agreed with the measured transmittance in the 45-150-? wavelength region. The calculated transmittance was significantly lower than that measured for the wavelength range 150-340 ?. This difference implies that molecular effects that are not accounted for by atomic-scattering factors become increasingly important at the longer wavelengths.     

Studies on the nonlinear optical single crystal: Ammonium d,l-tartrate (C4H9NO6)

The organic nonlinear optical material ammonium d,l-tartrate single crystal has been successfully grown by slow evaporation solution technique (SEST). The grown crystals were characterized by single crystal XRD and the lattice parameters have been confirmed. The structural perfection of the grown crystal was analyzed by high-resolution X-ray diffraction measurement. The optical transmittance spectrum shows that the material has a good optical transparency in the entire visible region with the UV cut-off wavelength at 234 nm. Thermogravimetric and differential scanning calorimetric measurements were performed to study the thermal properties of the grown crystal. Chemical etching studies were attempted to determine the dislocation density of the grown crystal. Mechanical behavior was assessed using Vickers hardness testing carried out on (0 0 1) crystallographic plane. The Kurtz–Perry powder SHG technique confirms the NLO property of the grown crystal and the efficiency of AMT crystal was found to be 1.3 times that of standard KDP crystal.     

Effect of Bi2O3 on physical, optical and structural properties of boron silicon bismuthate glasses

The lead-free boron silicon bismuthate glasses were investigated in terms of their physical, optical and structural properties. The physical properties of these glasses have been explored by compositional variation of X-ray diffraction (XRD), differential thermal analysis (DTA) and density. The optical properties of theses glasses have been investigated by UV–Vis and mid-infrared transmittance spectra, and refractive index. The structure of these glasses has been characterized by infrared (IR) absorption and Raman spectra.     

深紫外宽入射角范围增透膜设计与制备

在大数值孔径深紫外光学系统中,需要使用宽入射角范围的增透膜光学元件.选择LaF3和MgF2两种镀膜材料,设计了适用于深紫外宽入射角范围的三层、五层和七层三种增透膜系.实验使用热舟蒸发在熔融石英基底上镀制了设计的薄膜,并用紫外分光光度计对其光谱性能进行了测试,得到了在宽入射角范围内具有较高透过率的深紫外增透膜元件.双面镀五层增透膜系的熔石英基片在0°～55°入射角内的剩余反射率小于2.5％,在0°～20°入射角内的透过率大于98％.     

温度自适应红外热成像系统用硫系玻璃表面镀膜的研究进展

硫系玻璃具有透过谱段范围宽、折射率温度系数低等优点,是新一代温度自适应红外热成像光学系统的核心元件材料,应用前景十分广阔。为了满足不同服役环境的使用需求,须通过表面镀膜方式提升硫系玻璃的透过率和力学性能。介绍了国内外硫系玻璃表面镀膜的研究进展,在前期研究的基础上,总结归纳目前硫系玻璃镀膜存在的问题,并对硫系玻璃表面镀膜未来的发展方向做出预测。     

Comparative study of physical properties of vapor chopped and nonchopped Al2O3 thin films

Aluminium oxide being environmentally stable and having high transmittance is an interesting material for optoelectronics devices. Aluminium oxide thin films have been successfully deposited by hot water oxidation of vacuum evaporated aluminium thin films. The surface morphology, surface roughness, optical transmission, band gap, refractive index and intrinsic stress of Al₂O₃ thin films were studied. The cost effective vapor chopping technique was used. It was observed that, optical transmittance of vapor chopped Al₂O₃ thin film showed higher transmittance than the nonchopped film. The optical band gap of vapor chopped thin film was higher than the nonchopped Al₂O₃, whereas surface roughness and refractive index were lower due to vapor chopping.     

Control and characterization of structural and optical properties of ZnO thin films fabricated by thermal oxidation Zn metallic films

The physical properties of ZnO thin films fabricated by controlling thermal oxidation zinc metallic films process have been investigated. Comparative characterization of crystallographical, optical or spectroscopic properties of the samples was performed. The as-oxidized sample by rapid thermal process showed level of crystallinity degraded, higher optical transmittance in the visible and near-infrared region, and lower intensity of the near band edge emission compared to those prepared by conventional thermal oxidation. The overall results suggested that with in-depth understanding of the oxidation mechanism, rapid oxidation process could be employed as an approach to fabricate amorphous transparent oxide thin films from low-melting-point metals, which might have potential advantages in microelectronic and optoelectronic applications.     

Comparison of cadmium sulfide thin films deposited on glass and polyethylene terephthalate substrates with thermal evaporation for solar cell applications

Cadmium sulfide (CdS) thin films have been deposited onto glass and polyethylene terephthalate (PET) substrates at room temperature with thermal evaporation in a vacuum of about 3 × 10⁻⁵ Torr for use as window materials for solar cells. Effects of substrate types on the structural and optical characteristics of the films were studied. Sets of experiments were conducted to optimize the deposition of CdS films with appropriate deposition parameters. The deposited films were analyzed with atomic force microscopy, energy dispersive X-ray, X-ray diffraction and optical transmittance measurements to determine their structural and optical characteristics. X-ray diffraction patterns confirm the proper phase formation of the CdS. PET substrate exhibited the larger roughness than that for the glass because of large particles adsorbed on the PET substrate. The average transmittance of the films PET is about 71% and increases up to 81% for glass substrate.