pH‐response superabsorbant hydrogel synthesized by ultraviolet photopolymerization

A new synthesis method of pH‐response superabsorbent hydrogels (SHG) was achieved by direct ultraviolet (UV) photopolymerization, and in particular, the synthesis of SHGs of acrylic acid (AA), sodium acrylate (AANa), and methacrylcholine chloride (MACC) tricomponent copolymer by UV photopolymerization were investigated. The pH value responsive behavior of SHG with different monomer ratios of MACC and AA was researched, and SHG showed large swelling properties at pH value approximately 7. Influences of monomer ratio (mol) of AANa to AA, photoinitiators, crosslinking agents, and exposure time of UV light on the water absorbent properties were studied. The results showed that the water absorbent capacity of SHG based on photoinitiators: Esacure KTO46 or Irgacure 651 can reach comparatively high, N,N′‐Methylene bisacrylamide and diethylene glycol diacrylate (DEGDA) were high efficient crosslinking agents for its crosslinking the molecular chains through attending the copolymerization with monomers. When the exposure time was 10 min, the distilled water absorbency of SHG was 1503 mL/g under the condition: content of MACC, 14.3 wt %; monomer ratio (mol) of AANa to AA: 5.67; content of DEGDA and Irgacure 651, 0.0025 and 0.25 wt %. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1847–1852, 2007     

环氧豆油丙烯酸酯光固化速率的影响因素

将环氧大豆油与丙烯酸反应制备出环氧豆油丙烯酸酯预聚物,考察了光引发剂的种类、用量、辐射距离、时间及合成树脂的结构对光固化速率的影响,并利用红外光谱对树脂固化前后的结构进行了表征。研究结果表明,当辐射距离为20 cm时,光引发剂IHT-PI 184的用量为3%时固化速率最快,且随着酯化率的升高,固化速率加快,光固化后凝胶含量达到94.7%。     

光引发剂1-氯-4-丙氧基硫杂蒽酮的合成

1 氯 4 丙氧基硫杂蒽酮(1 chloro 4 propoxythioxanthone,CPTX)是一种重要的紫外光固化材料光引发剂。以邻巯基苯甲酸为原料,与对氯苯酚在浓硫酸中环合,得到中间体1 氯 4 羟基硫杂蒽酮,收率为97 1%。1 氯 4 羟基硫杂蒽酮、溴丙烷和碳酸钾在丁酮中回流,得到CPTX,收率为87 5%。综合两步反应,收率由文献的52 6%提高到84 9%。     

新型的含葡萄糖胺的水溶性高分子型硫杂蒽酮光引发剂

将硫杂蒽酮光引发剂（TX）和共引发剂葡萄糖胺（GA）引入同一个高分子链上,合成新型水溶性高分子型硫杂蒽酮光引发剂（PTX-GA）.通过改变PTX-GA中TX与GA的比例,合成了PTX-GA1、PTX-GA2、PTX-GA3,并通过光膨胀计实验研究了3种引发剂引发丙烯酰胺聚合的能力.研究表明这种水溶性高分子型硫杂蒽酮光引发剂即使在没有共引发剂胺的情况下,引发丙烯酰胺（AAM）的聚合效率也非常显著.同时由于它具有水溶性,而且含有生物分子,有利于改善光引发剂的生物相容性.     

丝印UV油墨光引发剂与颜料的匹配及用量研究

通过对以不同品种和用量光引发剂配制的四色丝印UV油墨固化速度的测试实验，分析了它们对油墨固化速度的影响，指出光引发剂的吸收波峰应尽可能在颜料对紫外光吸收较弱的波长范围内，并尽可能与紫外光源发射的主波长相近；根据本实验条件，光引发剂的用量约占油墨量的7％时，丝印UV油墨的固化速度最大。     

Photofabrication of biofiber‐based polymer matrix composites

The novel development of a photofabrication process of biofiber composites, based on oil palm empty fruit bunch fibers, is reported. The process consists of the following steps: (1) the preparation by a wet process of nonwoven mat of biofiber, either alone or in combination with glass and nylon; (2) drying the mat; (3) preparation of photocurable resin matrix, consisting of vinyl ester and photoinitiator; (4) impregnation of the mat by photocurable resin; and (5) irradiation of the impregnated mat by UV radiation to effect the cure of the composite. The nonwoven mat was formed in a “headbox” into which was poured a slurry of fibers. A wet mat was formed by after dewatering of the slurry. Biofiber, glass, and nylon fibers were mixed in different proportions. A “mixture experimental design” was used to generate experimental compositions of the reinforcing fibers and to model dependency of the response variables on the components through mathematical relationships. These relationships were meant to (1) determine the effect of composition of the reinforcing fibers on the physical and mechanical properties, (2) predict the response for any unknown composition of fibers, and (3) determine the optimum values of any identified properties. Because the product was characterized by multiple responses, simultaneous maximization of all properties was not feasible. The product must be considered in the definition of the trade‐off or compromise of properties to obtain overall satisfactory performance. Such an optimization was carried out and the results are reported. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1493–1499, 2005     

UV光固化胶黏剂

介绍了UV固化胶黏剂的主要类型与组成。     

含共引发剂胺的聚酯型高分子光引发剂的制备及其性能研究

为克服小分子光引发剂的固有缺陷,通过2-(2,3-二羟基)丙氧基硫杂蒽酮(HPTX)、二酰氯及N-甲基二乙醇胺(MDEA)进行逐步聚合反应,将硫杂蒽酮结构及共引发剂胺结构都引入到同一个高分子链上,制备了侧链含有硫杂蒽酮,主链含有共引发剂胺的聚酯型高分子光引发剂。傅里叶变换红外光谱(FT-IR)和核磁共振氢谱(1H-NMR)证实了高分子光引发剂的结构。紫外光谱(UV-Vis)证实了高分子的结构对硫杂蒽酮单元的最大紫外吸收几乎没有影响。用光致差示扫描量热仪(photo-DSC)研究聚酯型高分子光引发剂引发聚酯丙烯酸酯树脂(PEA)的光聚合反应,结果表明:高分子光引发剂的主链结构对其引发效率有着显著的影响。     

有机硅树脂的紫外光固化及其固化膜性能研究

利用水解缩合的方法,将聚甲基三乙氧基硅烷(PTS)、二甲基二乙氧基硅烷(DDS)和γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)在盐酸(HCl)的催化作用下进行反应,制备出一种可UV固化有机硅树脂预聚物,通过FT-IR、29Si-NMR对预聚物的光固化过程和缩合程度进行了表征;同时研究了固化膜的热性能、表面能、耐水性、耐乙醇性、硬度、附着力等.研究结果表明:紫外光固化30 s后,有机硅预聚物的双键转化率达到了95.89％,UV固化有机硅涂膜失质量5％和15％对应的温度T5％和T15％分别为194.9℃和261.8℃;固化膜的表面能为16.36 mJ/m2.     

UV curable EA-Si hybrid coatings prepared by combination of radical and cationic photopolymerization

A series of UV curable EA-Si hybrid coatings were prepared by a simple approach combining radical and cationic photopolymerization, with epoxy acrylate (EA) as monomer, γ-glycidoxypropyltrimethoxysilane (GPTMS) as inorganic precursor, benzophenone (BP) as free radical photo initiator and a diaryliodonium salt DPIHFP as cationic photo initiator. The chemical structures of EA-Si hybrid coatings were characterized by Fourier transform infrared (FTIR), Raman spectroscopy and X-ray diffraction (XRD). The thermal and optical properties of hybrid coatings were investigated by thermal gravimetric analysis (TGA) and UV–vis transmission spectroscopy, respectively. The results indicated that cross-linked network structure of SiOSi formed in the hybrid coatings, which led to the decrease in crystallinity and of EA-Si hybrid coating. The final conversion of CC bonds was also decreased because of the addition of GPTMS. The thermal stability of EA-Si hybrid coatings was enhanced in the second decomposition stage (300–400 °C) because of the existence of organic–inorganic cross-linked network structures. The transparency of coatings at around 346 nm tended to increase with increasing concentration of inorganic precursor GPTMS.