原位聚合法研制纳米胶囊相变材料

采用超声波工艺及细乳液原位聚合方法,研制了以聚苯乙烯为囊壁、正十八烷为囊芯的纳米胶囊相变材料;系统探讨了聚合反应各因素如引发剂、链转移剂、表面活性剂以及正十八烷/苯乙烯比等对乳胶粒子的形态、胶囊材料热性能的影响,对所研制的胶囊相变材料进行激光衍射粒度分析、透射电镜及差示扫描量热等表征.实验结果表明,在引发剂AIBN 0.5%(油相质量百分比,下同);链转移荆DD在T0.4%;复合乳化剂(SDS/OP10)总量2%,配比1:1及正十八烷/苯乙烯比=1:1条件下,胶囊呈球形均匀分布,聚苯乙烯囊壁能将正十八烷囊芯很好包裹住,其胶囊Z均直径124nm,相变焓可达124.4kJ·kg-1.     

Continuous emulsion polymerization of vinyl acetate. II Operation in a single Couette–Taylor vortex flow reactor using sodium lauryl sulfate as emulsifier

Continuous emulsion polymerizations of vinyl acetate were conducted at 50°C in a single continuous Couette–Taylor vortex flow reactor (CCTVFR) using sodium lauryl sulfate as emulsifier and potassium persulfate as initiator. The polymerization can be carried out very smoothly and stably, but the steady‐state monomer conversion attained in a CCTVFR is not as high as that in a plug flow reactor (PFR), but only slightly higher than that in a continuous stirred tank reactor (CSTR), even if the Taylor number is adjusted to an optimum value. Also, the effects of operating variables, such as the emulsifier, initiator, and monomer concentrations in the feed and the mean residence time on the kinetic behaviors were almost the same as those observed in a CSTR. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2755–2762, 2002     

超细纤维素胶体和丙烯酰胺的接枝共聚

本文用纤维素材料经酸分解制备具有平衡聚合度（LODP）的微晶纤维素，再分散成超细纤维素胶体（准均相纤维素体系）。用扫描电镜（SEM）观察处理前后的纤维素颗粒尺寸，并比较它们和丙烯酰胺接枝共聚的反应速率、聚合转化率、接枝率、接技效率、聚丙烯酰胺支链的分子量及其分布的情况。     

Simulation of Fe-Al compounds developed during single superphosphate manufacture

In order to analyse iron phosphate complexes and gel-like phases encountered in the single superphosphate process, experiments were performed with a free-Al, Fe apatite crystal of Durango from Mexico phosphate rock and sulfuric acid. Reaction products were studied by X-ray diffraction and surface analysis methods namely X-ray photoelectron spectroscopy and scanning electron microscopy. Results show that in a free Al, Fe-system, part of the Ca(H₂PO₄ )₂.H₂O (MCPM) forms before precipitation of any CaSO₄(CS) and gel-like phase such H₂SO₄.yH₃PO₄.xH₂O is formed. When iron is added, the precipitation rate of (CS) and (MCPM) increases and Fe₃(H₃O)H₈(PO₄)₆.6H₂O is formed. When Fe and Al are added, a gel-like phase is quickly formed with a molar ratio that changes with time and develops into crystalline compounds. The composition of this gel may be represented as a mixture of two phases: H₂SO₄.yH₃PO₄.xH₂O and a gel containing Al-Fe-Si.     

金属闪光外墙乳胶漆的研制及性能研究

以丙烯酸酯及有机硅单体为原料合成了核-壳型硅丙乳液,用自制分散剂将闪光铝粉分散成水性闪光铝粉浆,并成功分散于硅丙乳液中,加入进口助剂,配制成水性金属闪光外墙乳胶漆.讨论了基料的玻璃化温度、单体的加入方式、引发剂、乳化剂、反应温度、聚合工艺和pH等对乳胶漆性能的影响.     

新型技术用于乳状液膜法脱酚的进一步研究

本文对模拟的含酚废水,采用新型技术对乳状液膜法脱酚进行了进一步的探讨。对所采用的制乳设备———撞击流-旋转填料床对制乳率、提取设备———旋转填料床对脱酚率、破乳设备———无机微孔膜法破乳的重要参数(如透过压方式、膜孔径等对膜通量和破乳率的影响)进行了研究。并且讨论了破乳后的油相回用情况。实验结果表明:撞击流-旋转填料床的制乳效率可达99.90 %以上,脱酚率可达99%左右,且瞬间完成;膜孔径越小,破乳率越高,膜通量越小;外压内抽方式的破乳效果优于单外压方式的破乳效果。对于粒径为5～2 5 μm乳液,用膜孔径为2 .0 μm的SiC微孔膜,在外压为6 0kPa、内负压为30kPa的外压内抽破乳方式下破乳,破乳率可达96 .4 % ,膜通量可达90 0L·(m2 ·h) -1。     

Oxidative flavour deterioration of fish oil enriched milk

The oxidative deterioration of milk emulsions supplemented with 1.5 wt‐% fish oil was investigated by sensory evaluation and by determining the peroxide value and volatile oxidation products after cold storage. Two types of milk emulsions were produced, one with a highly unsaturated tuna oil (38 wt‐% of n‐3 fatty acids) and one with cod liver oil (26 wt‐% of n‐3 fatty acids). The effect of added calcium disodium ethylenediaminetetraacetate (EDTA) on oxidation was also investigated. Emulsions based on cod liver oil with a slightly elevated peroxide value (1.5 meq/kg) oxidised significantly faster than the tuna oil emulsions, having a lower initial peroxide value (0.1 meq/kg). In the tuna oil emulsions the fishy off‐flavour could not be detected throughout the storage period. Addition of 5—50 ppm EDTA significantly reduced the development of volatile oxidation products in the cod liver oil emulsions, indicating that metal chelation with EDTA could inhibit the decomposition of lipid hydroperoxides in these emulsions. This study showed that an oxidatively stable milk emulsion containing highly polyunsaturated tuna fish oil could be prepared without significant fishy off‐flavour development upon storage, provided that the initial peroxide value was sufficiently low.     

整形美容外科用新材料—─瘢痕软化用硅胶纱布膜

本文研究了硅胶纱布膜的制备方法和治疗效果。在增生性瘢痕的治疗中，硅凝胶能较快地软化和减轻瘢痕，其治疗时间要比加压疗法短。目前，对硅凝胶的作用机理尚未完全明了，但一般认为水化和封闭是治疗作用的主要基础     

负离子乳胶漆的研究及应用进展

介绍了空气中负离子的作用、负离子乳胶漆释放负离子的原理和国内外负离子乳胶漆产品的研发进展。     

高效乙烯聚合催化剂的制备——I．催化剂的制备规律

研究了新型含镁络合物的结构、性质及其用于制备高效乙烯聚合催化剂的制备规律。结果表明：将镁、有机醇以及不与镁发生“格式反应”的卤代烷相互作用可迅速发生反应形成新型含镁络合物溶液。该络合物在溶液中可析出结晶。具有特定的化学结构．可以均匀承载于多孔硅胶的孔隙中，负载TiCl4后制备出形态良好的球形高效乙烯集合催化剂。