绿色化工产品固体光气的合成及应用

固体光气是近年来迅速发展的绿色化工产品,主要通过碳酸二甲酯的光催化氯化反应合成,有四氯化碳溶剂法和碳酸二甲酯本体法工艺。它是工业广泛使用的剧毒羰基化试剂光气的理想代替品,可以与醇、胺、羧酸、醛和酰胺等化合物反应,替代光气制备多种重要有机化合物,在有机合成、医药、农药、染料、高分子材料等领域具有广泛的应用前景。     

氯化聚丙烯熔点与氯化度的关系研究

以甲苯为溶剂,过氧化二苯甲酰(BPO)为引发剂,通过自由基聚合,对聚丙烯(PP)进行氯化改性;研究了PP氯化改性熔点与氯化度的关系,模拟出了氯化聚丙烯(CPP)氯化度与熔点之间的关系模型,该模型为CPP的氯化度的测定提供了一种较为简便的方法     

Selective Chlorination of Side-chains in Friedel-Crafts Polymers

Aralkyl polymers with ethyl side-chains were prepared by Friedel-Crafts reactions. Ethylbenzene and bis(p-chloromethyl)benzene (BCMB) were reacted together in the presence of stannic chloride to produce polymers of various molecular weights. A study was then carried out of the chlorination of these polymers, using (a) molecular chlorine, (b) molecular chlorine with a peroxide catalyst and phosphorus pentachloride, (c) sulphuryl chloride. The objective was to determine the best conditions for chlorination to occur selectively at the α-carbon atom of the ethyl group, with minimal chlorination at either the β-position or the main-chain methylene groups. Analysis of ¹H nuclear magnetic resonance spectra of the chlorinated polymers suggests that in most cases chlorination occurs extensively both in the side-chain and in the main-chain methylene groups. Conditions were found, however, which favour chlorination at the α-position. The greatest selectivity was achieved when molecular chlorine, a peroxide catalyst and phosphorus pentachloride were used in benzene solvent.     

催化还原技术处理水溶液中氯代有机物的实验研究

以四氯化碳和四氯乙烷为代表物,研究了水溶液中氯代烷烃的催化还原脱氯技术,使用的还原剂为废铁刨花并添加催化剂和极化材料．结果表明该方法能使氯代有机物在零价铁体系中有效地发生还原反应,能迅速脱氯为氯离子,降低氯代有机物的毒性。探讨了有机物浓度对反应速率的影响,并分析了还原脱氯速率和反应中间产物,四氯化碳的反应产物主要是二氯甲烷,而1,1,2,2-四氯乙烷的主要反应产物是二氯乙烯。氯代有机物直接得到电子而发生还原脱氯是其主要反应机理。     

氯化聚丙烯的制备与性能研究

本文针对聚丙烯(PP)粘合性差、较难染色、低温呈脆性、收缩率大等缺陷,采用溶液法对聚丙烯进行氯化改性,以AIBN(BPO)为引发剂,氯苯为溶剂,进行自由基引发接枝反应制取氯化聚丙烯(CPP)。通过滴定法得出氯化度的值,并对反应时间、反应温度、引发剂浓度等条件进行考察,得出最优氯化工艺条件,采用红外技术(FT-IR)对CPP加以表征,从溶解性能方面加以分析,进一步阐述了氯化度对其性能的影响。实验结果表明,该法可以得到氯原子的接枝产物,在反应温度120℃,反应时间5h时,CPP的氯化度最高可达52%,氯化度越高溶解度越高。     

无溶剂光氯化悬浮法制备低氯化度的氯化等规聚丙烯

用无溶剂光氯化悬浮法进行等规聚丙烯 (IPP)氯化反应 ,考察了反应时间、引发剂、通氯量、悬浮剂和金属盐等因素对氯化速度的影响 ,以偶氮二异丁腈为引发剂 ,m(IPP)∶m(H2 O) =1∶1 5,通氯量为 40mL min ,反应时间 1 0h ,可得到氯质量分数在 2 5%左右的氯化聚丙烯。金属离子可明显缩短其诱导期 ,但反应后期 ,金属离子的存在对氯化反应起抑制作用。     

氯化熔盐体系黏度特性研究现状

中国钛原料钙镁含量高,主要采用熔盐氯化法处理,会产生大量废盐难以处理。研究氯化熔盐体系的黏度特性对于开发该工艺产生的大量废盐利用新方法具有重要意义。综述了国内外对氯化熔盐体系黏度影响规律的研究：从氯化熔盐体系的熔盐离子出发,探讨了Ca²⁺、Mg²⁺、Na⁺及K⁺等对氯化熔盐黏度的影响;从反应条件出发,探讨了温度、气氛和添加剂对氯化熔盐黏度的影响。结合当前对氯化熔盐体系黏度的研究,针对NaCl-KCl-CaCl₂-MgCl₂四元氯化熔盐体系,在不同温度条件下改变气氛或者添加剂,对体系黏度的变化规律进行了考察。通过改变氯化熔盐体系的黏度,寻求适合高温相转化渣高效分离的手段和方法,对高温相转化法高效循环处理熔盐氯化废渣具有重要意义,并能有效推动中国熔盐氯化法的发展。     

Compatibility among chlorinated polyethylenes

Compatibility among chlorinated polyethylenes with different degrees of chlorination has been identified by the transparency of blended films cast from solvent. Dynamic mechanical measurements have been used to check these observations. The heats of mixing of pairs of chlorinated octadecanes with different degrees of chlorination have been measured and shown to be positive. It has been found that in this system, which is dominated by dispersion forces, compatibility is determined by similarity of the equation-of-state parameters. The Flory equation-of-state theory without the interaction entropy parameter Q₁₂ generates a positive ΔG_m and hence fails to predict compatibility. A positive Q₁₂ is needed to remedy this deficiency of the theory. This is in direct contrast to the negative Q₁₂ which is introduced in the systems which are dominated by specific interactions.     

Regioselektive C-H-Funktionalisierung von Fettsäuren und Fettsäuremethylestern

Regioselective C-H-Functionalization of Fatty Acids and their Methyl Esters Fatty acids and thier methyl esters can be chlorinated preferentially at the terminal methylene groups with N-alkylchloroamines in sulfuric acid. With capric acid and its methyl ester the optimal reaction conditions for the selective chlorination were elaborated and then transferred to longer fatty acids up to stearic acid. The influence of the solvent, the temperature and the nature of different chlorinating reagents on the selectivity was studies. The capillary GC/MS-analysis of the isomeric chlorinated fatty acids is described.     

光氯化法氯化石蜡-52生产新工艺的研究和应用

研究开发了生产氯化石蜡-52的光催化氯化新工艺,该工艺具有反应速度快、反应温度低、能量消耗少、产品质量稳定、氯气利用率高和操作便利、安全可靠等优点,适宜热氯化工艺生产氯化石蜡-52的技改工程,已成功地用于工业化生产。     

In situ chlorination of poly(vinyl chloride) in aqueous hydrochloric acid

Based on environmental, safety, corrosion and technological considerations a new method has been developed for chlorination of PVC in aqueous hydrochloric acid solvent by controlled electrolytic in situ generation of chlorine using graphite and chlorine-selective Ti-RuO₂ electrodes. The byproduct, HCl gas, is dissolved at the moment of its formation and acts as starting material of further chlorination. This way, the application of corrosive chlorine gas is avoided. The chlorination conditions have been optimized. The highest chlorine content was found at 5.5 h reaction time using a graphite electrode. The obtained chlorinated PVC did not contain any CCl₂ units.     

Hyperchlorinated fatty acids: II. Photochlorination of stearic acid in carbon tetrachloride,reaction study

The free radical chlorination of stearic acid in carbon tetrachloride was studied with variation of the chlorine flow rate, the active light intensity and the initial fatty acid concentration. In addition the variation of temperature with time was measured. The chlorine flow rate affects only the reaction time and modifies neither the chlorine content of the products obtained nor the yield, approximating 100%. On the other hand, the initial fatty acid concentration seems to be the prime factor determining the chlorine content of the products. Similarly, the onset of the polymerization of the chlorinated monomers depends essentially on the initial fatty acid concentration. These polymers are probably chlorinated polyesters. This behavior can be explained by the incursion of radical ions RCOO·⁺ resulting from irradiation of exciplexes formed by interaction between the more or less highly chlorinated fatty acid and the solvent. These interactions take place when the fundamental complex occupies a critical volume, which depends on the acid concentration.     

2,4-二氯-5-硝基苯酚合成中四氯化碳替换的研究

从产物收率、溶剂回收率、操作安全性等方面研究了用氯仿替换四氯化碳作为溶剂合成2,4-二氯-5-硝基苯酚的方法,解决了禁用四氯化碳的问题。     

聚丙烯水相悬浮热氯化

研究了等规聚丙烯(IPP)水相悬浮热氯化,考察了氯化时间和温度、IPP粒径、搅拌转速、通氯速率等条件对氯化反应的影响。发现氯含量随氯化温度的升高而增大,随IPP粒径的减小而呈线性增大;在IPP充分分散条件下搅拌和通氯速率对氯化几无影响。扫描电镜(SEM)照片显示,氯化反应首先发生在粒子表面,氯化产物将粒子表面孔隙填充,增加了氯向粒子内部扩散的阻力,致使粒子内部的氯化反应缓慢。     

Electron-beam lithography of chlorinated polystyrenes with narrow molecular weight distributions

Polystyrenes with narrow molecular weight distributions have been chlorinated with only slight broadening of molecular weight distributions to yield materials that are five to six times more sensitive to electron-beam irradiation. The chlorinated polystyrenes are useful negative resists for electron-beam lithography. At molecular weights of 3-4 × 10⁵g/mole, their threshold sensitivities to 20 keV electrons are 1-2μC/cm². Their lithographic contrasts are ≥ 1.5; in fact, > 2.0 for the narrowest molecular weight distributions. They compare favorably in these regards to polystyrenes of similar molecular weight characteristics. Lithographic relief images that are 80% of the original thickness of the polymer film can be formed at three to four times the threshold dose. The degree of chlorination ranged from 0.65-0.76 Cl/monomer unit. The infrared spectra of the chlorinated materials resemble the spectrum for poly(4-chlorostyrene). Elemental analysis indicated, however that some addition of chlorine had occurred. More extensive chlorination or chlorination of the higher molecular weight starting materials broadened the molecular weight distributions. The chlorinated material, a kind of poly(4-chlorostyrene-costyrene), is less sensitive than poly(4-chlorostyrenc) prepared by addition polymerization by almost a factor of four.     

A CASE STUDY FOR CONTROL STRUCTURE SELECTION: CHLORINATION STAGE IN THE BLEACHING PROCESS OF A PULP AND PAPER PLANT

The minimization of chlorinated organic compounds in the effluents of the chlorination unit of a pulp mill is proposed by the use of a control structure for the chlorination unit. Bleached pulp properties are related to the unbleached pulp properties: lignin content, brightness, and viscosity, as well as the amount of chlorinated organics in the bleachery effluent. The best feasible control pairings are studied by RGA and SVD methods. Kappa number of the bleached pulp (a measure of lignin content) and percent consistency of the pulp to be bleached; residual chlorine (which affects the amount of chlorinated organics discharged) and percent chlorine/pulp ratio adapted in the chlorination stage; and exit pulp viscosity (which directly affects strength and tear resistance of the paper) and residence time in the chlorinator are chosen to be the best pairings.     

Surface modification of synthetic vulcanized rubber

Surface modifications produced by treatments (mainly halogenation) of synthetic vulcanized styrene-butadiene rubber (SBR) leading to increased adhesion properties with polyurethane adhesives have been studied. T-peel tests, scanning electron microscopy (SEM), advancing contact angle measurements, infra-red (IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and differential scanning calorimetry (DSC) were used to analyze the nature of surface modifications produced in the rubber. Although some surface heterogeneities were created, physical treatments (ultrasonic cleaning, solvent wiping, abrasion) did not noticeably increase the adhesion strength because certain abhesive substances (e.g. zinc stearate, paraffin wax) cannot be removed from the rubber surface by such treatments. Chemical treatment (chlorination) was carried out using ethyl acetate solutions of trichloroisocyanuric acid (TCI) (1,3,5-trichloro-1,3,5-triazine-2,4,6-trione). Chlorination of SBR with trichloroisocyanuric acid produced a significant improvement in T-peel strength, due to the contribution of mechanical (surface roughness, microcracks), thermodynamical (increase of polar contribution to the surface energy) and chemical (removal of abhesive substances, creation of polar groups) rubber surface modifications. The strong adhesion between the chlorinated SBR surface and the polyurethane adhesive was due to the presence of oxidized species of >C=O, -C-OH and -COR type. Chlorination of SBR is a fast reaction which needs only a small concentration of chlorination agent (< 1 wt% TCI/ethyl acetate) to produce high adhesion levels. An increased amount of TCI facilitated the chlorination reaction progressing from the exterior to the internal rubber bulk; however, although a thicker layer of chlorinated rubber created no further increase in adhesion strength was obtained.     

关于改善水相法氯化石蜡-70产品色泽的探讨

从原料、生产过程(主要包括氯化、中和、水洗、干燥)等方面分析了水相悬浮氯化法生产的氯化石蜡-70产品色泽深的原因.通过实验确定了生产色泽佳的产品的操作方法.     

聚电解质静电沉积改性制备高性能反渗透膜

利用次氯酸钠溶液对商品反渗透膜表面进行氯化处理,然后将聚阳离子电解质壳聚糖通过静电吸附作用沉积在RO膜的表面,系统地研究了氯化过程的pH、氯化时间、次氯酸钠浓度、壳聚糖浓度及其沉积时间对膜性能的影响,以制备出高通量、高截留率的RO膜。在压力1.55 MPa、原料液温度（298±1）K的条件下,测定RO膜处理2000 μg·g^-1氯化钠溶液的水通量和截留率。结果表明,当pH=9、氯化时间为30 min、次氯酸钠浓度为1000 mg·L^-1时,水通量较原膜提高了约19.89%,截留率略有提高;当壳聚糖浓度为0.1%（质量分数）、沉积时间为30 min时,改性膜的接触角降低到34.88°,亲水性提高,水通量较氯化后的RO膜几乎保持不变,为60.55 L·m^-2·h^-1,截留率达到了99.56%。经过氯化和沉积改性后的RO膜水通量和截留率均得到了提高。     

氯化酶解木质素的合成与性能研究

以酶解木质素为原料,在水相条件下通入氯气合成氯化木质素。考察了木质素与水的配比、有无紫外光催化、反应温度和通氯量对产物得率和氯含量的影响,并对产物进行了红外光谱和热重分析。结果表明,在氯气过量的情况下,产物氯含量达到29.8%,有紫外光催化时产物氯含量比较低,不加热时的产物氯含量更高,产物氯含量随氯气的增加而增大。氯化木质素的红外光谱图在1720cm-1处羰基强度明显增强,680cm-1附近出现C-Cl的特征吸收峰,说明Cl2与酶解木质素发生了取代反应。热重分析结果表明,氯化木质素的耐热性比酶解木质素稍差。与PVC共混改性的结果表明,氯化木质素改善了原有木质素分子的极性,有望作为极性高聚物共混改性的相容剂使用。