用∑WESH图评价某涂料化工厂的可持续性

介绍了在清洁生产过程中用∑WESH图评价涂料化工厂的可持续发展的原理及方法,并进行了一个实例的评价.从该厂的∑WESH图得出该厂的水及能源的利用率高,所用的原材料的稀缺性都不大,唯一较严重的问题是二甲苯的通过量大,危害性较严重.因此建议该厂在配方上尽量减少二甲苯的使用,开发新产品.     

喷涂前处理污染源的分析及其处理措施

随着我国国民经济的快速发展和国家"节能减排"重点项目的深入开展,各种污染源的分析及其处理措施的研究备受关注.本文在充分研究若干家电企业的钢铁喷涂制件的前处理工艺(如:预脱脂、脱脂、清洗、表调、磷化等)的基础上,分析喷涂前处理过程中的污染源,研究污染源的处理措施.     

酿酒酵母细胞表达异源萜类化合物的研究进展

萜类化合物具有可观的经济价值,但是目前的生产过程复杂、产量低。酿酒酵母甲羟戊酸途径为萜类化合物的合成提供直接前体,因此酿酒酵母细胞具有合成异源萜类化合物的天然优势。对酿酒酵母甲羟戊酸途径的清晰认识是对其进行有效利用的基础,本文从代谢途径、关键酶的特点和全局调控机制3个方面对该途径进行了介绍。从代谢途径的构建和优化、模块与底盘细胞的适配、模块构建及组装方式的角度概述了酿酒酵母细胞异源合成单萜、倍半烯萜、二萜、三萜类化合物的研究进展。指出实现酿酒酵母高效合成萜类化合物所需要解决的基础问题是对酿酒酵母甲羟戊酸途径进行更为全面了解和对萜类化合物的天然代谢途径进行明确解析;另外,合成生物学的进一步发展也将为此提供应用基础。     

香叶油的研究进展

为了全面了解香叶油的研究现状,为我国香叶油的开发利用提供思路, 综述了香叶的栽培、组培技术研究、香叶油的应用、香叶油的提取及化学成分研究、香叶油调配研究等方面的现状,并对香叶品种的遗传改良提出一些有益的建议.     

胶原纤维的性能特点和作用

1胶原纤维巴西Novaprom胶原纤维是以精选的牛皮内剖层(真皮)组织提取的,它不同于明胶或明胶的衍生物。它的生产是在严格控制的时间和温度范围内进行的,从而确保其主要成分──胶原蛋白的活性不变,并以天然纤维的形式存在。它在肉制品中的结构呈纤维状而不是一般的胶冻,因而这种结构是非常稳定的,是不可逆的。它是很好的功能性动物纤维蛋白,在肉制品及鱼糜制品等相关的食品中得到广泛的应用。2胶原纤维的性能及相关指标(1)蛋白质含量:胶原纤维中的动物蛋白质(M×6.25)高达98%,含有人体必需的氨基酸。(2)吸水、持水性:胶原纤维结构良好,呈矩…     

鲜为人知的科学珍闻

有言在先,珍闻的挑选奉行以下原则:科学应该是有趣的,科学之所以好玩,部分原因在于你了解、知道这些奇谈怪论的存在。科学的伟大之处在于,它不必是教条的、有价值的实验,也不要求对所有理论进行最准确的过滤以得     

玻璃纤维拉丝池窑配合料设备研制的进展

玻璃纤维池窑拉丝生产线配合料的制备中,原料是形成优质玻璃液的基础,因此可以说配合料的稳定性、均匀性和准确性对玻璃纤维的质量起着决定的作用.生产实践证明:组分和粒度均匀的配合料,不但能强化玻璃液的熔化和澄清过程,而且还能减少或消除影响玻璃质量的各种弊病.所以认真拟定玻璃纤维原料的成分和选择玻璃纤维的种类和化学性质:严格控制进厂原料化学成分、粒度和水份;做好原料的分堆、存放、加工、称量、混合、输送是优质配合料制备不可缺少的手段,这也是做好玻璃纤维池窑配合料的基本任务.     

氢氧化镁阻燃剂的研究进展

主要论述了国内外阻燃剂的种类和发展,指出由于环境和健康的原因,无机阻燃剂是最有发展前途的,其中的氢氧化镁因其特有的性质,在无机阻燃剂中尤为突出.考虑到氢氧化镁的广泛应用的前景和其本身的缺点,对其改性成为业界的研究重点,其中主要介绍了钛酸酯、硬脂酸(盐)、镁盐晶须和胶囊化等技术,指出以后的发展方向是在改性基础上的协同作用.     

高浸透性大分子聚酯乳液的研制

1前言 随着池窑生产的发展,原有的浸润剂在快速浸润性和快速浸透性方面无法得到满足.意大利DSM公司聚酯乳液是公认的喷射纱浸润剂最好的成膜剂.本项目的目的是研制出能工业化生产的与DSM公司产品质量相当的聚酯乳液,替代进口,节约外汇,满足我国池窑发展需要,争创良好的经济社会效益.     

宁静——使艺术深华

宁静的山是心灵的绘画,宁静的水是灵魂的诗篇,宁静的夜是精神的书籍。在这越来越充斥着物欲纵横的社会,浮躁成了现代人的代名词,而保持一颗宁静的心,尤其在艺术创作中显得尤为重要。     

Studies on mechanical behavior high impact polystyrene/vinyl clay nanocomposites: Comparison between in situ polymerization and melt mixing

A comparative study on various synthesis methods like melt mixing (MM) and in situ polymerization (ISP) of high impact polystyrene/vinyl clay nanocomposites (HIPS/VNCs) is attempted here. In ISP, nanocomposites were prepared by mixing vinyl clay (VC) and poly butadiene rubber (PBR) in styrene with the initiator, azo bis isobutyronitryle. Melt compounding was conducted in two ways–commercial melt mixed blend where Commercial HIPS was mixed with VC and in situ melt mixed blend, where, nanocomposites were prepared by mixing polystyrene, PBR, and VC. The effect of dispersion of the nanoclay on the morphology and material properties of HIPS/VNCs was compared for all the methods, and it is found that the product obtained by ISP gives better properties when compared with MM. Moreover, the dispersion of the clay in the matrix is greater by in situ method, which is evident from X‐ray diffraction pattern and scanning electron microscopic analysis. Statistical analysis of ISP was carried out by design expert software version 8.0.7.1. Modeling and Optimization of the mechanical properties were done by using central composite design of response surface methodology. POLYM. COMPOS., 38:68–76, 2017. © 2015 Society of Plastics Engineers     

Preparation of the HIPS/MA graft copolymer and its compatibilization in HIPS/PA1010 blends

The graft copolymer of high‐impact polystyrene (HIPS) grafted with maleic anhydride (MA) (HIPS‐g‐MA) was prepared with melt mixing in the presence of a free‐radical initiator. The grafting reaction was confirmed by infrared analyses, and the amount of MA grafted on HIPS was evaluated by a titration method. 1–5% of MA can be grafted on HIPS. HIPS‐g‐MA is miscible with HIPS. Its anhydride group can react with polyamide 1010 (PA1010) during melt mixing of the two components. The compatibility of HIPS‐g‐MA in the HIPS/PA1010 blends was evident. Evidence of reactions in the blends was confirmed in the morphology and mechanical behavior of the blends. A significant reduction in domain size was observed because of the compatibilization of HIPS‐g‐MA in the blends of HIPS and PA1010. The tensile mechanical properties of the prepared blends were investigated, and the fracture surfaces of the blends were examined by means of the scanning electron microscope. The improved adhesion in a 15% HIPS/75% PA1010 blend with 10% HIPS‐g‐MA copolymer was detected. The morphology of fibrillar ligaments formed by PA1010 connecting HIPS particles was observed. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2017–2025, 1999     

Flame retardant and the degradation mechanism of high impact polystyrene/Fe-montmorillonite nanocomposites

High impact polystyrene/Fe-montmorillonite (HIPS/Fe-MMT) nanocomposites were successfully prepared by melting intercalation. The nanostructures of HIPS/Fe-MMT were testified by X-ray diffraction (XRD) and transmission electron microscope (TEM). Corresponding to pure HIPS, the thermal stability of HIPS/Fe-MMT nanocomposites was notably improved. The peaks of heat release rate (PHRR) and the mass loss rate (MLR) were significantly reduced after the formation of the HIPS/Fe-MMT nanocomposites from cone calorimetry. And nanocomposites PHRR was further lower with the increase of Fe-MMT content in the range of 1 to 5 wt%. The degradation mechanism of HIPS and HIPS/Fe-MMT nanocomposites was conducted by pyrolysis gas chromatography mass spectrometry (Py-GC-MS). And the reason of the enhancement of thermal stability maybe is that structural iron is the operative site for radical trapping in the Fe-MMT and the nanostructure enhances the interaction of the chains of the HIPS.     

Poly1‐hexene: New impact modifier in HIPS technology

Poly1‐hexene was prepared using a conventional heterogeneous Ziegler–Natta catalyst and its stereoregularity was characterized using ¹³C‐NMR analysis. New kind of high impact polystyrene (HIPS) was prepared by radical polymerization of styrene in the presence of different amounts of synthesized poly1‐hexene (PH) as impact modifier (HIPS/PH) and compared with conventional high impact polystyrene with polybutadiene (HIPS/PB) as rubber phase. Scanning electron microscopy (SEM) revealed that the dispersion of poly1‐hexene in polystyrene matrix was more uniform compared with it in HIPS/PB. The impact strength of HIPS/PH was 29–79% and 80–289% higher than that in HIPS/PB and neat polystyrene, respectively. FTIR was used to confirm more durability of HIPS/PH samples toward ozonation. To study the effect of rubber type and amount on the T_gs of polystyrene, differential scanning calorimetry was employed. Results obtained from TGA demonstrated higher thermal stability of HIPS/PH sample in comparison with conventional HIPS/PB one. Our obtained results suggest new high impact polystyrene that in all studied aspects has better performance than the conventional HIPS. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43882.     

HIPS/蒙脱土复合材料炭层结构对阻燃性能的影响

采用熔融插层法制备了不同有机蒙脱土(OMMT)及无机蒙脱土(MMT)含量的HIPS/OMMT和HIPS/MMT复合材料,并通过锥形量热仪评价了复合材料的阻燃性能;采用数码相机、扫描电镜(SEM)观察了燃烧残余物结构。结果表明,OMMT的加入显著提高了HIPS/OMMT复合材料阻燃性,而MMT的加入,HIPS/MMT复合材料的阻燃性能提高不明显。HIPS/OMMT复合材料燃烧结束形成了皮层-蜂窝层复合的炭渣结构,对其阻燃性有重要的影响。     

ABS/HIPS共混材料的改性研究

研究了(丙烯腈/丁二烯/苯乙烯)共聚物(ABS)与高抗冲聚苯乙烯(HIPS)质量比对ABS/HIPS共混材料力学性能和加工流动性的影响,并着重对质量比分别为80/20和70/30的两种ABS/HIPS共混材料进行了改性研究。结果表明,氯化聚乙烯(PE-C)、(苯乙烯/丁二烯/苯乙烯)嵌段共聚物(SBS)和K树脂对ABS/HIPS共混材料有不同程度的增容增韧改性作用。如采用9份PE-C与3份SBS并用改性的ABS/HIPS(70/30)共混材料的拉伸强度为27.04MPa,冲击强度为32.60kJ/m2,比改性前约提高2.7倍。转矩流变仪分析表明,PE-C、SBS和K树脂改性的ABS/HIPS共混材料加工流动性和稳定性良好。维卡软化温度测试表明,改性后ABS/HIPS共混材料的耐热性能略有降低,但影响不大。扫描电子显微镜照片清晰反映出改性后ABS与HIPS两相的相容性得到了改善。     

HIPS/纳米蒙脱土复合材料的研究

添加不同种类，不同数量的纳米蒙脱土，混炼制得HIPS／纳米蒙脱土复合材料，以改善高抗冲聚苯乙烯（HIPS）的性能，测试了其力学性能，热稳定性性。结果表明，添加3％烘干的蒙脱土Cloisite 30A的HIPS／纳米蒙脱土复合材料具有较好的综合力学性能，可作为工程塑料使用；HIPS／纳米蒙脱土复合材料的热稳定性与阻燃性有所改善，添加5％烘干的蒙脱土Cloisite 15A的HIPS／纳米蒙脱土复合材料具有较好的阻燃性。     

Novel methods for synthesis of high‐impact polystyrene with bimodal distribution of rubber particle size

By using in situ prepolymerization and radiation curing, high‐impact polystyrene (HIPS) with a bimodal distribution of the size of the rubber particles (bimodal HIPS) was synthesized in the presence of ultrafine full‐vulcanized powdered styrene–butadiene rubber (UFPSBR) and polybutadiene rubber (BR). TEM photographs indicated that UFPSBR was dispersed uniformly as a single particle with a diameter of about 100 nm. On the other hand, bimodal HIPS with different rubber particle size distributions could also be obtained by blending HIPS and UFPSBR grafting styrene (UFPSBR‐g‐St) with different grafting yields. The bimodal HIPS with the smallest rubber particle size, at about 100 nm, could be prepared by blending the monomodal HIPS containing big rubber particles with polystyrene/UFPSBR. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

HIPS/OMMT复合材料炭渣结构对阻燃性能的影响

采用熔融插层法制备了高抗冲聚苯乙烯/有机蒙脱土(HIPS/OMMT)和高抗冲聚苯乙烯/蒙脱土(HIPS/MMT)复合材料,并通过锥形量热仪评价了复合材料的阻燃性能;采用数码相机、扫描电镜(SEM)观察了燃烧残余物结构,对残余物结构进行了热重(TGA)分析。结果表明:OMMT的加入显著提高了复合材料以热释放速率表征的阻燃性能,而HIPS/MMT复合材料的阻燃性能提高不明显;HIPS/OMMT纳米复合材料燃烧热释放速率峰值时形成了皮窝复合炭渣结构,皮层组分主要为硅酸盐及部分难分解的碳质物质,热稳定性较高,窝层起膨胀炭层的作用,二者共同起阻燃作用。     

Non-Isothermal Crystallization of High-Impact Polystyrene/Poly(Phenylene Sulfide) Blends

The morphology of isothermally crystallized poly(phenylene sulfide) (PPS) and a blend combining it with high-impact polystyrene (HIPS) were observed through a polarized optical microscope equipped with a CSS450 hot-stage. The crystalline superstructure of PPS is mainly spherulite, and it was found that the presence of HIPS has little influence on the morphology of PPS, but decreases the nucleation rate of PPS. The effect of HIPS on the non-isothermal crystallization of PPS was investigated by differential scanning calorimetry (DSC). The maximum and onset crystallization temperatures for the HIPS/PPS blend were about 10°C lower than those of neat PPS, which indicates that the crystallization of PPS was retarded by HIPS. The Ozawa model was used to analyze the non-isothermal crystallization kinetics of PPS and its blends. The Avrami exponent values of neat PPS were higher than those of its blend, which shows that the presence of HIPS changed both the nucleation rate and the crystallization rate of PPS.