LED封装用透明环氧树脂的改性

选用不同种类的光稳定剂对发光二极管(LED)封装用透明环氧树脂进行改性,研究了光稳定剂对环氧树脂透光率和耐紫外线老化性能的影响。所选用的光稳定剂与环氧树脂都具有良好的相容性.采用苯并三唑类光稳定剂UV-329改性环氧树脂和受阻胺类光稳定剂HS-508改性环氧树脂封装的LED比采用普通环氧树脂EP-400封装的LED寿命分别提高59%和73%。HS-508与UV-329共同使用具有协同作用,采用最优条件改性环氧树脂封装的LED的寿命比用EP-400封装的LED提高了170%。     

受阻胺光稳定剂和抗氧剂并用对聚合物紫外光稳定性的影响

阐述了受阻胺稳定剂(HALS)和抗氧剂的分类和作用机理,重点介绍了受阻胺类光稳定剂和抗氧剂并用对聚合物紫外光降解中的影响。当受阻胺类光稳定剂和抗氧剂并用时,既有协同效应,又有对抗效应,也有加和效应。这依赖于受阻胺类光稳定剂和抗氧剂的种类。同时介绍受阻胺光稳定剂发展的趋势。     

聚氨酯材料的降解与稳定化研究进展

综述了聚氨酯树脂（PU）的降解和稳定化机理。由于聚氨酯光稳定性的制约，限制其应用范围，选用适宜的稳定剂，可明显改善其光稳定性，从而可用于户外。本文介绍了各种稳定剂（抗氧剂，紫外线吸收剂，受阻胺光稳定剂（HALS））。讨论了各种稳定剂对改善聚氨酯光稳定性的情况，结果表明，同时使用上述稳定剂可取得较好的结果。     

加氢润滑油基础油光稳定剂的研制

应用正交试验设计的方法,研究了自制的紫外辐射吸收剂、受阻胺类光稳定剂及抗氧剂对兰州石化总厂生产的125N加氢润滑油基础油抗光氧化降解性能的影响.发现以上各种添加剂均能提高加氢润滑油基础油抗光氧化降解的能力.在相同的辐射剂量下,添加四甲基受阻胺类光稳定剂的加氢基础油抗光氧化降解的能力优于添加五甲基受阻胺类光稳定剂;添加苯并三唑型紫外辐射吸收剂比添加二苯甲酮型紫外吸收剂的加氢基础油抗光氧化降解的能力强;紫外辐射吸收剂与受阻胺类光稳定剂之间以及紫外辐射吸收剂与抗氧剂之间均存在协同作用.并且发现,四甲基受阻胺类光稳定剂与酚类抗氧剂之间存在协同作用,而五甲基受阻胺类光稳定剂与酚类抗氧剂之间存在反协同作用.评价结果表明:添加自制的高效无灰复合型光稳定剂1.5g·L-1可使兰州炼油化工总厂生产的125N加氢润滑油基础油保持良好的光稳定性,其透光率、色度均优于添加2 g·L-1目前最好的有机镍盐配合物型光稳定剂.     

耐侯性环氧树脂的研究进展

综述了耐侯性环氧树脂的研究进展,论述了在环氧树脂中加入抗氧剂和光稳定剂的方法,介绍了上述稳定剂的种类及应用结果。     

聚甲醛耐光稳定性研究进展

综述了聚甲醛光氧老化特性和光稳定剂研究开发现状,指出了聚甲醛光稳定剂未来发展趋势。聚甲醛对抗紫外光稳定性较差,容易发生降解与氧化,添加光稳定剂有助于提高聚甲醛耐光稳定性。常用的聚甲醛光稳定剂主要包括紫外光屏蔽剂、紫外光吸收剂和受阻胺类光稳定剂等三大类,对光稳定剂的研究方向主要包括高相对分子质量化、聚合物键合化、多功能化、受阻胺低碱性化等方面。     

不饱和聚酯树脂的降解与稳定化研究进展

综述了不饱和聚酯树脂（UP）的降解机理，UP光稳定性较差，限制了其应用范围，添加适宜的稳定剂可明显改进其光稳定性，从而可用于户外。本文介绍了一些抗氧剂、紫外线吸收剂、受阻胺光稳定剂（HALS）。试验表明，只使用单一的稳定剂效果不佳，必须将主抗氧剂，辅抗氧剂和其他添加剂（例如：某些环氧化合物）并用，才能取得较好的稳定效果。     

抗紫外光环氧树脂的研究进展

综述了国内外的抗紫外环氧树脂的研究进展：研究结果表明,添加紫外线吸收剂和抗氧剂后可明显提高环氧树脂的光稳定性,并使之可用于LED,此外,稳定剂配合使用时效果更好。     

聚氨酯材料的降解机理及其稳定剂

综述了聚氨酯(PU)材料的光降解、热氧化降解、水解等降解机理,以及用作光稳定剂、热氧化稳定剂、水解稳定剂的产品种类及其协调作用.聚氨酯材料的使用环境不同,降解机理也不同,正确选用稳定剂并进行应用是提高PU材料性能的一种简单而有效的手段.     

功能母料中耐老化体系的选择(Ⅱ)

2 光稳定剂 2.1 受阻胺 受阻胺是最常用的光稳定剂,在氧化后产生哌啶氮氧自由基.哌啶氮氧自由基活性较大,能与树脂中降解物烷基自由基、烷氧自由基反应,产生哌啶烷基胺醚和哌啶基过氧化胺醚,中止树脂的降解.     

LED封装用改性环氧树脂研究进展

传统的LED环氧树脂封装材料存在脆性大、耐冲击性差、容易老化、透光率低、折射率低等缺陷,限制了其在LED封装产业中的应用,通过环氧树脂改性可弥补其作为LED封装材料的缺陷。本文综述了近年来LED环氧树脂封装材料在高折射率、光稳定、抗黄变、有机硅改性方面的研究进展,并展望了LED改性环氧树脂封装材料的发展前景。     

环氧丙烯酸树脂合成工艺的改进

探讨了以环氧树脂和丙烯酸为原料的酯化反应,合成了紫外光固化的环氧丙烯酸树脂。通过研究催化剂、阻聚剂的种类、加入量、聚合方式、加料方式、反应温度等因素对转化率的影响,得到了合成环氧丙烯酸树脂的较佳工艺条件。并用IR对环氧树脂与环氧丙烯酸树脂的结构进行了表征。     

阻燃抑烟环氧树脂的合成及其性质

以磷酸、三聚氰胺、尿素为原料制备阻燃抑烟剂聚磷酰氰胺脲,然后将其应用于TDE-85#环氧树脂中,以顺丁烯二酸酐为固化剂制备了阻燃抑烟环氧树脂。研究了阻燃抑烟剂聚磷酰氰胺脲的吸湿性,纯环氧树脂和阻燃抑烟环氧树脂的极限氧指数、UL-94阻燃性、隔热性能、烧蚀速率和透光率等。研究结果表明,聚磷酰氰胺脲对环氧树脂具有非常优异的阻燃、抑烟功效。     

环氧树脂的稳定化(Ⅰ) 环氧树脂的老化研究进展

综述了环氧树脂的老化过程、老化机理、老化过程研究方法及研究进展 ,还论述了促使环氧树脂老化的各种因素 ,如环氧树脂分子结构、环境条件、水的浸蚀、环氧树脂固化条件及固化程度等因素 ,为环氧树脂防老化研究提供了理论基础     

Effect of amino‐functionalization of multi‐walled carbon nanotubes on the dispersion with epoxy resin matrix

Amino‐functionalization of multiwalled carbon nanotubes (MWCNTs) was carried out by grafting triethylenetetramine (TETA) on the surfaces of MWCNTs through the acid–thionyl chloride way. The amino‐functionalized MWCNTs show improved compatibility with epoxy resin and, as a result, more homogenous dispersion in the matrix. The mechanical, optical, and thermal properties of the amino‐functionalized MWCNT/epoxy composites were also investigated. It was found that introducing the amino‐functionalized MWCNTs into epoxy resin greatly increased the charpy impact strength, glass transition temperature, and initial decomposing temperature of cured epoxy resin. In addition, introducing unfunctionalized MWCNTs into epoxy resin was found greatly depressing the light transmission properties, which would affirmatively confine the application of the MWCNTs/epoxy composites in the future, while much higher light transmittance than that of unfunctionalized MWCNTs/epoxy composites was found for amino‐functionalized MWCNTs/epoxy composites. SEM of the impact cross section and TEM of ultrathin film of the amino‐functionalized MWCNTs/epoxy composites showed that the amino‐functionalized MWCNTs were wetted well by epoxy matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 97–104, 2006     

Effect of epoxy resin on morphology and physical properties of PVC/organophilic montmorillonite nanocomposites

Poly(vinyl chloride)/organophilic montmorillonite (PVC/OMMT) nanocomposites were prepared by means of melt blending. A liquid epoxy resin was used to aid PVC chains in intercalating into silicate layers. The effects of the preparation methods and epoxy resin contents on the melt intercalation of PVC were investigated. The morphology development, mechanical properties and optical properties of the PVC/OMMT composites were tested as functions of epoxy resin content and OMMT content. Wide‐angle X‐ray diffraction, transmission electron microscopy and scanning electron microscopy were used to characterize the morphology of the resulting composites. After being pretreated by the epoxy resin, the OMMT layers were largely intercalated into the PVC matrix, and even exfoliated at high epoxy resin content. The addition of epoxy resin led to a decrease in optical clarity of the composites but improved the processing stability, as indicated by yellowness index and haze measurement. However, the optical clarity of the composites containing 4 phr of epoxy resin (PVC/E‐OMMT) was improved by increasing the OMMT content, as shown by light transmission. Both the tensile strength and notched Izod impact strength of the PVC/E‐OMMT composites reached their maximum values when the OMMT content was 0.5 phr and the epoxy resin content was 2 phr. With further increase of the OMMT content and the epoxy resin content, the tensile strength decreased but was still higher than that of original PVC. The method of addition of epoxy resin had little effect on the physical properties but mainly influenced the morphology of PVC/OMMT nanocomposites. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2184–2191, 2003     

环氧树脂的稳定化(Ⅱ) 环氧树脂光防护研究进展

论述了环氧树脂光防护研究进展 ,论述了加入抗氧剂和光稳定方法 ,介绍了紫外线吸收剂种类及工业应用结果。     

Mechanical properties of an epoxy resin toughened by polyester

The epoxy resins were toughened by 4–24 phr polyester with average molecular weight 1.9×10⁴ g/mol in this investigation. The mechanical properties were examined and dynamic mechanics analyses were performed for the epoxy resins before and after the modification. The toughening mechanism of polyester to epoxy resin is discussed in light of the scanning electronic microscopy observation of the fracture surfaces. The results showed that the impact strength and tensile strength of the modified epoxy resin were remarkably greater than those of the unmodified cured epoxy resin. The most suitable composition for the modified epoxy resin was the addition of 16 phr polyester, which led to 138 and 46% increments in the impact strength and the tensile strength, respectively. And the mechanical properties depended greatly on the congregating state of polyester added. The polyester dispersing in the epoxy matrix was amorphous when its addition was less than or equal to 12 phr, and was sphere crystals when the addition was over 16 phr. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3384–3389, 2003