非光气法合成溴代聚碳酸酯系列阻燃剂的研究

采用碳酸双(三氯甲)酯(简称BTC)代替剧毒光气合成溴代聚碳酸酯(简称BPC)系列阻燃剂,研究了溶剂、碱、催化剂、反应温度、结晶剂对合成溴代聚碳酸酯的影响、反应时间与催化剂用量的关系、溴代聚碳酸酯相对分子质量的控制.结果表明,最佳工艺条件是:溶剂为A或B,用量为每摩尔TBA1.5～2.5 L;碱用量为每摩尔TBA 2.8～3.5 mol,浓度为5%;催化剂为BTMA,用量为每摩尔TBA 10～40 g;反应时间2～6 h;反应温度10～60 ℃;结晶剂为C,用量为溶剂A或B的3倍(体积);作为阻燃剂,溴代聚碳酸酯的相对分子质量为2 500～6 500,通过调节TBA与BTC的配比及相对分子质量调节剂的用量来实现.     

界面缩聚法合成四溴双酚A聚碳酸酯的工艺研究

以光气和四溴双酚A(TBBPA)为原料经光气界面缩聚,合成了四溴双酚A聚碳酸酯,并对四溴双酚A与光气投料比、催化剂种类及其用量、分子量调节剂用量4个因素进行考察。优化工艺条件为:四丁基氢氧化铵为催化剂,对叔丁基酚(TBP)为分子量调节剂,n(四溴双酚A)∶n(光气)=1∶1.3,n(四溴双酚A)∶n(对叔丁基酚)=1∶0.028,n(四溴双酚A)∶n(四丁基氢氧化铵)=1∶0.022。该方法操作简单,产品分子量分布窄,易于工业化生产。     

纤维素大分子引发剂的制备与表征

以阔叶浆纤维素为原料,2-溴异丁酰溴(BIBB)作溴化试剂,4-二甲氨基吡啶(DMAP)作催化剂,二氯甲烷(DCM)作为溶剂的反应体系中,制备纤维素大分子引发剂Cellulose-Br。探究反应时间、反应温度、溴化试剂用量、催化剂用量对大分子引发剂取代度(DS)的影响,并通过正交试验,确定了制备大分子引发剂的最佳工艺条件为反应温度为35℃、反应时间为32 h、溴化试剂与纤维素的摩尔比为5.5:1、催化剂与溴化试剂的摩尔比为0.6:1,产品取代度达到了0.94。红外光谱表明大分子引发剂的合成是通过酯化反应完成的。     

3,6-二溴咔唑的合成工艺改进

3,6-二溴咔唑是重要的医药中间体,本文采用N-溴代丁二酰亚胺法、液溴法和硅胶法三种方法合成了3,6-二溴咔唑,实验结果表明,硅胶法为较佳路线,并通过正交实验得出最优工艺条件为：室温下反应时间为12h,原料咔唑、N-溴代丁二酰亚胺、溶剂二氯甲烷、催化剂硅胶的用量物质的量比为1：2：131：47时,产品平均收率可提高到89．25％。同时,通过单因素实验对原料配比、反应时间、溶剂用量和催化剂用量四种因素对反应的影响进行了研究。     

高性能覆铜板用溴化环氧树脂的合成研究

以萘酚和甲醛缩合，得到平均分子量在300-2000之间的多羟基萘酚酚醛树脂（NPN），NPN再与环氧氯丙烷（ECH）进行环氧化反应，然后再与四溴双酚A（TBBA）进行扩链反应，合成得到了高性能溴化萘酚酚醛环氧树脂（ENPNB）。探讨了最佳实验条件为：萘酚酚醛树脂的合成温度在100℃左右，反应时间4h；合成萘酚酚醛环氧树脂的反应温度在90℃左右，真空度约0.07MPa，反应时间为8h，碱的摩尔数为酚羟基当量的0.9-1.1倍；含溴萘酚酚醛环氧树脂的反应温度为150℃。控制TBBA/ENPN摩尔比为1：2，反应时间为4h，产物的固化以DDS为固化剂，2-MI作促进剂，在真空度为0.1MPa，温度为190℃的恒温干燥箱中固化130min。     

3-溴甲基-3-甲基氧杂环丁烷的合成

以2,2-二溴甲基丙醇（BBMP）为初始原料,通过与碱发生关环反应生成3-溴甲基-3-甲基氧杂环丁烷（BrMMO）。讨论了碱的种类和用量对BBMP关环产率的影响以及反应体系中碱的浓度、反应温度和反应时间对合成BrMMO产率的影响。通过实验确定的最佳工艺条件为：BBMP与NaOH摩尔比为1.0∶1.1,NaOH醇溶液的质量分数为12%,反应温度为78℃,反应时间为4h时,BrMMO产率为65%。最终产品经元素分析、IR和1HNMR检测确定为BrMMO。该试验工艺简单,原料易得,且溶剂便于回收、污染小。     

溴代聚碳酸酯类阻燃剂

聚溴代碳酸酯（溴代PC）类阻燃剂是完全用四溴双酚A替代双酚A制成的纯溴代PC齐聚物．其用途不是作为阻燃材料直接加工成制品，而是作为聚合物的阻燃助剂。作为一种溴系阻燃剂，溴代PC阻燃剂属于溴含量较低（〈60％）的一类，它具有热稳定性高、渗出量少、加工性能优异、对树脂的物理性能影响较少、不腐蚀等优点。例如。聚酯（PET和PBT）中约40％的聚酯为阻燃级产品。     

硅胶催化合成3,6-二溴咔唑

以咔唑、N-溴代丁二酰亚胺(NBS)为原料,硅胶为催化剂,合成3,6-二溴咔唑,考察了反应时间、原料配比、溶剂用量和催化剂用量对反应的影响。正交实验表明,较佳工艺条件为:咔唑、NBS的摩尔比为1∶2,二氯甲烷50 mL,硅胶17 g时,室温下反应12 h,收率达89.25%,熔点为213.5℃。产物结构经TLC、IR进行表征。     

11-溴代十一酸的合成研究

11-溴代十一酸是尼龙 - 11单体的中间体 ,以 10 -十一烯酸和溴化氢为原料合成 11-溴代十一酸 ,通过实验得出了溴代反应的最佳工艺条件为 :引发剂用量 2 % ,溴代温度 0～ 15℃ ,反应时间 1h ,溶剂为甲苯 ,10 -十一烯酸与甲苯的最佳配比 2 0 % ,上述条件下 ,溴代反应的收率达 92 %以上     

相转移催化法合成1,4-二丁氧基苯

以水为溶剂,在相转移催化剂四丁基溴化铵和氢氧化钾存在的条件下,对苯二酚和溴代正丁烷反应合成了1,4-二丁氧基苯。通过对水的用量、相转移催化剂种类及用量和反应时间的考察,得出了较适宜的合成条件:对苯二酚0.1 mol,溴代正丁烷0.21 mol,氢氧化钾0.21 mol,水10 mL,相转移催化剂四丁基溴化铵用量为1.5 mmol,反应时间4 h,所得产率可达94%。     

Copolymerization of CO2 and epoxides catalyzed by metal salen complexes

The design of efficient metal catalysts for the selective coupling of epoxides and carbon dioxide to afford completely alternating copolymers has made significant gains over the past decade. Hence, it is becoming increasingly clear that this "greener" route to polycarbonates has the potential to supplement or supplant current processes for the production of these important thermoplastics, which involve the condensation polymerization of diols and phosgene or organic carbonates. On the basis of the experiences in our laboratory, this Account summarizes our efforts at optimizing (salen)CrIIIX catalysts for the selective formation of polycarbonates from alicyclic and aliphatic epoxides with CO2. An iterative catalyst design process is employed in which the salen ligand, initiator, cocatalyst, and reaction conditions are systematically varied, with the reaction rates and product selectivity being monitored by in situ infrared spectroscopy.     

Aliphatic polycarbonate synthesis by copolymerization of carbon dioxide with epoxides over double metal cyanide catalysts prepared by using ZnX2 (X = F, Cl, Br, I)

As means of the chemical fixation of carbon dioxide and the synthesis polycarbonates, copolymerizations of carbon dioxide with various epoxides, such as cyclohexene oxide, cyclopentene oxide and propylene oxide were investigated in the presence of double metal cyanide (DMC) catalysts. The DMC catalysts were prepared by reacting K₃Co(CN)₆ with ZnX₂ (X = F, Cl, Br, I) together with tertiary butyl alcohol and poly(tetramethylene ether glycol) as complexing reagents and were characterized by various spectroscopic methods. The DMC catalysts showed high activity for epoxides and CO₂ copolymerization to yield aliphatic polycarbonates of narrow polydispersity and moderate molecular weight.     

Non‐catalyst synthesis and thermal behaviors of three‐arm star aliphatic polycarbonates

Three‐arm star aliphatic polycarbonates (TMP‐PDTCs) were successfully synthesized via the ring‐opening polymerization of 2,2‐dimethyl trimethylene carbonate (DTC) initiated by trimethylolpropane (TMP) in the absence of catalysts. The structure of TMP‐PDTCs was characterized by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and gel permeation chromatography (GPC). The effects of reaction temperature, time, and the DTC/TMP molar feed ratio on the non‐catalyst polymerization were investigated. The thermal behaviors of TMP‐PDTCs were measured by differential scanning calorimetry (DSC). © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41998.     

Effect of cocatalyst and carbon dioxide pressure on the synthesis of polycarbonate from phenyl glycidyl ether and carbon dioxide

The copolymerization of phenyl glycidyl ether (PGE) and carbon dioxide was performed in the presence of ionic liquid catalyst. 1-Butyl-3-methyl imidazolium chloride, tetrabutylamouim chloride and 1-n-butylpyridinium chloride were used as catalyst for this reaction carried out in a batch reactor. All the ionic liquid catalysts showed good catalytic activity for the synthesis of polycarbonates with very low polydispersity, close to 1. The carbonate content, turnover number (TON), and average molecular weight of the copolymer were affected by the structure of the ionic liquid. High carbon dioxide pressure enhanced TON and carbonate content because of the increase of carbon dioxide absorption in PGE solution. ZnBr₂ and a Zn-Co cyanide complex were also tested as a catalyst and/or cocatalyst for this reaction to compare their catalytic performance with the imidazolium salt ionic liquids.     

Metallocorroles as Electrocatalysts for the Oxygen Reduction Reaction (ORR)

The oxygen reduction reaction (ORR) is the most important reaction in life processes and in energy transformation, such as fuel cells. Normally, the ORR in a fuel cell is very slow and a cathode ORR catalyst is needed to reach a practical usable level. Pt-based materials are the most effective catalysts, but they are too expensive to make fuel cells commercially viable and hence extensive research has focused on developing alternative catalysts. First row transition metallocorroles are potent catalysts for many reactions, and they may eventually be used as true alternatives to the precious metals currently used. Regarding ORR, brominated cobalt corrole has been shown to operate almost as well as an industry standard platinum-based catalyst. In this review, we would like to summarize the progress that has been made in this field.     

溴化环氧树脂合成新工艺

以四溴双酚A(TBBPA)与环氧氯丙烷为原料,通过对溴化环氧树脂(EP)合成工艺的改进,并配合使用自制的催化剂,成功合成了高相对分子质量(Mw)的溴化EP。研究了催化剂的种类及用量、反应溶剂、反应体系浓度、反应温度和反应时间等对溴化EP合成反应的影响规律。试验结果表明:当w(自制催化剂)=0.2%(相对于物料而言)、以环己酮为溶剂、反应体系初始浓度为75%(反应一段时间后稀释至60%)、180～190℃反应8.5h时,所得溴化EP产品的Mw为6.02×104、Mw分布窄、其热稳定性良好且产品质量与国外同类产品相当。     

Vacuum and Pressured Combinatorial Processings for Exploration of Environmental Catalysts

Two types of combinatorial chemical reactors have been developed for high-throughput experimentation of catalysts that attract much interest from global environmental viewpoints. The high vacuum combinatorial laser MBE system was applied to the preparation of thin film library of TiO₂ with its film thickness gradually increased, which resulted in the discovery of new phenomenon indicating a quantum size effect in TiO₂ photo-catalysis. The combinatorial autoclave reactor was made to explore new catalysts and optimum reaction conditions efficiently for alternating CO₂ copolymerization with epoxide (oxirane) to form bio-degradable polycarbonates. Some preliminary results are reported on the CO₂ copolymerization with propylene oxide, as a means of CO₂ fixation into chemically useful material.     

Carbon-dioxide-derived unsaturated alicyclic polycarbonate: Synthesis,characterization, and post-polymerization modification

A facile pathway for functionalizing carbon dioxide (CO₂) derived alicyclic polycarbonates has been developed by the combination of CO₂–unsaturated alicyclic epoxide alternating copolymerization and subsequent post-polymerization modification. Thus, poly(cyclohexadiene carbonate) (PCHDC) was synthesized by the alternating copolymerization of CO₂ and 1,4-cyclohexadiene-1,2-oxide with tetraphenylporphyrinatocobalt(III) chloride/dimethylaminopyridine. The subsequent post-polymerization modification of PCHDC by bromine addition to double bonds efficiently proceeded to afford the brominated polycarbonate, i.e., poly(dibromocyclohexene carbonate). The effect of post-polymerization modification on their thermal properties was further examined through thermal gravimetric and differential scanning calorimetry analyses.     

Synthesis,Characterization, and Glass Reinforcement of Flame Retardant Acrylated Poly(Ester-Amide) and Flame Retardant Poly(Ester-Imide) Resins Based on Brominated Epoxy Resin

Bisphthalamic acids were prepared by reaction of phthalic anhydride and aliphatic diamines. Flame retardant poly(ester-amide)s were prepared by reaction of brominated epoxy resin with bisphthalamic acids and post reaction was carried out with acryloyl chloride to obtained acrylated flame retardant poly(ester-amide) resins. Bismaleimides were prepared by reaction between aromatic diamines and maleic anhydride. Carboxy terminated bismaleimides were prepared by Michael addition reaction of bismaleimides and 4-amino benzoic acid. Flame retardant poly(ester-imide)s were prepared by reaction between carboxy terminated bismaleimides and brominated epoxy resin. All the obtained products were characterized and analyzed by making composites.     

碱在合成溴化环氧树脂阻燃剂中的关键作用

研究了碱在四溴双酚A和环氧氯丙烷(相转移催化条件下)缩聚生成高分子量溴化环氧树脂阻燃剂过程中的作用。结果显示:合成溴化环氧树脂过程中,分别选用四乙基溴化铵、四甲基溴化铵、聚乙二醇(分子量6,000和分子量400)等相转移催化体系,LiOH、NaOH、KOH等对环氧树脂产品(分子量、收率和Br含量)产生显著影响并且影响程度差异较大,LiOH效果最好,KOH次之,NaOH最差。碱用量以保证得到预期产品的前提下最低用量为宜。