The thermal stability investigation of microencapsulated ammonium polyphosphate/siloxane‐modified epoxy resin composites

In this investigation, epoxy resin composites containing phosphate and silicone were prepared from microencapsulated ammonium polyphosphate (MFAPP) and poly(methylphenyl siloxane) (PMPS). Silicone‐containing epoxy (E‐S) copolymers were gained by the grafting reaction between ? OCH₃ of PMPS and ? OH of E51. And, a fixed weight of MFAPP was introduced to epoxy systems via the physical blending method. The chemical structure of the E‐S copolymer was determined by Fourier transform infrared spectroscopy (FTIR) and ¹H‐NMR. The impact testing results revealed that the impact toughness was improved slightly. The thermogravimetric analysis (TGA) results demonstrated that the thermal degradation property in high temperature region and solid residue yield at 800 °C were enhanced remarkably with increasing PMPS content, whether the testing atmosphere was in nitrogen or oxygen. Moreover, an obvious synergistic effect of silicon and phosphorus on promoting the thermo‐oxidative degradation stability and solid residue at 800 °C was proved. Furthermore, the scanning electron microscope micrographs and FTIR result of residual charred crusts of EA‐S systems after the TGA testing in air manifested that the bubbled charred layer and silicon‐ and phosphorus‐containing residue took chief responsibility for thermo‐oxidative degradation property and solid residue yield. So the MFAPP/siloxane‐modified epoxy resin composites have a significant development prospect in high‐temperature resistant organic adhesives and coatings. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45272.     

微胶囊材料在涂料中的应用

简介了微胶囊材料的性能特点及制备方法,分析了微胶囊材料在涂料行业特别是特种功能型涂料领域内的应用,指出了微胶囊材料在涂料行业中广泛的应用前景。     

In-vivo analysis of angiogenesis and revascularization of transplanted pancreatic islets using confocal microscopy

A technique to measure angiogenesis and revascularization in pancreatic islets transplanted at the renal subcapsular site in the rat has been developed. In-vivo imaging of the microcirculation of transplanted pancreatic islets was conducted using a confocal scanning laser microscope (CSLM) to achieve optical sectioning through the graft in order to perform a computer reconstruction of the three-dimensional neovascular morphology. Individual islets were harvested by enzymatic digestion of excised pancreas from Fischer 344 rats. Isolated islets were cultured for 24 h, and approximately 300–350 islets were transplanted at the renal subcapsular site of the left kidney in an anaesthetized rat. Six to 14 days post-transplantation, the animal was anaesthetized and prepared for in-vivo imaging of the microvasculature on a Zeiss LSM-10. Optical contrast of the microvasculature was enhanced by the administration of fluorescein-labelled dextran into the circulating blood. The transplant site was identified and serial sections were obtained through the vascular bed at varying z-intervals. Complementary fluorescence video images were also obtained via a silicon intensifier tube camera mounted on the CSLM. At completion of the imaging procedure, the kidney was returned into the body cavity, the area was sutured and the animal was allowed to recuperate for subsequent examinations. Image processing algorithms, such as grey-level thresholding, median filtering, skeletonization and template matching, were applied to compute the vessel density and diameters and extrapolated to measure 3-D vessel lengths and the tortousity index of the neovasculature.     

Synthesis and properties of microencapsulated phase change material with a urea–formaldehyde resin shell and paraffin wax core

During this study, paraffin wax with low melting point was encapsulated in a urea–formaldehyde resin to prepare a novel microencapsulated phase change material (Micro-P6) for temperature regulation and thermal energy storage. The structure and properties of Micro-P6 were characterized by using Fourier transform infrared spectroscopy, differential scanning calorimeter, laser particle size analyzer, thermogravimetric analysis, contact angle analysis, and scanning electron microscope. The results indicated that the chemical structure of Micro-P6 meets the designed core–shell structure; and the paraffin wax with low melting point was successfully encapsulated by using urea–formaldehyde resin; and the Micro-P6 shows a spherical structure and rough surface, and the average size is 8.0–10.0 μm. Then, the performances of Micro-P6, such as core content, mechanical property, thermal conductivity and durability, were tested. Based on above characterization and performance test, it was indicated that the synthesized Micro-P6 could be used in the field of cementing and construction for temperature regulation and thermal energy storage. The applications of Micro-P6 in the field of cementing and construction will be completed in our next study. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48578.     

聚乙烯/杨木粉基木塑复合材料的性能研究

目的 研究硅烷偶联剂(KH-550)处理木粉以及微胶囊红磷(HP)阻燃对木塑复合材料(WPC)的性能影响.方法 以杨木粉、低密度聚乙烯(LDPE)、线性低密度聚乙烯(LLDPE)和HP为原料,采用二次共混造粒及注射模塑法,制备WPC,通过熔体流动速率(MFR)试验、拉伸试验、TGA谱图分析、Kissinger动力学分析和SEM显微观察研究WPC的性能.结果 采用KH-550处理木粉后,体系的MFR提高了0.01 g/min,拉伸时的最大位移提高了2.59 mm,HP的添加使WPC在分解5％和50％时的温度分别提高了18℃和54℃,KH-550和HP共改性的WPC在420～500℃(主要分解阶段)的表观活化能为153 kJ/mol.结论 采用KH-550处理杨木粉后,使体系的拉伸性能得到有效改善,在添加质量分数为10％的HP后,WPC的阻燃效果得到显著提高.     

Apoptosis in Type 2 Diabetes: Can It Be Prevented? Hippo Pathway Prospects

Diabetes mellitus is a heterogeneous disease of complex etiology and pathogenesis. Hyperglycemia leads to many serious complications, but also directly initiates the process of β cell apoptosis. A potential strategy for the preservation of pancreatic β cells in diabetes may be to inhibit the implementation of pro-apoptotic pathways or to enhance the action of pancreatic protective factors. The Hippo signaling pathway is proposed and selected as a target to manipulate the activity of its core proteins in therapy-basic research. MST1 and LATS2, as major upstream signaling kinases of the Hippo pathway, are considered as target candidates for pharmacologically induced tissue regeneration and inhibition of apoptosis. Manipulating the activity of components of the Hippo pathway offers a wide range of possibilities, and thus is a potential tool in the treatment of diabetes and the regeneration of β cells. Therefore, it is important to fully understand the processes involved in apoptosis in diabetic states and completely characterize the role of this pathway in diabetes. Therapy consisting of slowing down or stopping the mechanisms of apoptosis may be an important direction of diabetes treatment in the future.     

可预涂微胶囊型厌氧胶的性能

可预涂微胶囊型厌氧胶是汽车等工业生产线上使用的重要胶粘剂,本文对其相关的一些性能特别是GAY系列和GY－560的工艺性能进行了简介。     

微胶囊技术在蓄热调温纺织品中的应用

本文简要介绍了微胶囊技术的发展概况 ,叙述了蓄热微胶囊技术在新型智能纺织品———蓄热调温纤维、织物和泡沫方面的应用。蓄热调温纺织品将对改善人类的穿着舒适性产生一定的影响     

西藏酥油及其粉末油脂在贮存期间过氧化值的变化

建立三氯甲烷-冰乙酸(2:3)混合溶剂超声振荡破壁提油的新方法,提油时间为15min.根据建立的新方法对西藏酥油粉末油脂破壁提油后,用滴定碘量法测定过氧化值,以评价不同贮存期西藏酥油及其粉末油脂过氧化值的变化.结果表明,西藏酥油粉末油脂的过氧化值在6个月内变化不大,从最初的3.67meq/kg升高到9.69meq/kg,呈升高的趋势,但仍然符合国家对食用油过氧化值的要求;西藏酥油则不同,其过氧化值从1.64 meq/kg迅速增大到72.83 meq/kg,然后下降,说明微胶囊化对油脂能起到很好的保护作用.     

微胶囊化红磷阻燃剂的制备及其在玻纤增强尼龙66中的应用

为克服红磷直接应用于玻纤增强尼龙66中的缺点,研究了用原位聚合法制备微胶囊红磷的工艺,测试了样品的吸湿性以及表面包覆性能,并研究了其用于玻纤增强尼龙66的阻燃性能和力学性能。结果表明,制得的微胶囊化红磷应用于玻纤增强尼龙66中,不仅具有优良的阻燃性能(FV 0级),而且力学性能比单独应用红磷有所提高,加工工艺性能有较大幅度的提高。