以二氧化碳为原料制备聚合物-王启录-117143(共18页)

1、以二氧化碳(r yng hu tn)为原料制备聚合物姓名(xngmng)：王启录 班级(bnj)：高分子C112 学号：117143中国知网：二氧化碳合成可降解塑料的发展综述 钱伯章(上海擎督信息科技公司，上海 200127)摘 要:介绍了国外二氧化碳（CO2）合成可降解塑料的发展状况；分析了该产品在推广应用中存在的成本压力大、销售难、投资风险大等难题；认为以二氧化碳合成的高分子材料具有生物可降解的特性，属于环境友好材料，是目前高分子技术领域重要的发展方向之一。关键词:二氧化碳;可降解塑料;环境友好中图分类号:X384 文献标志码:A 文章编号:1006-5377（2011）01-0038-0

2、5Development Report on Degradable Plastic of CO2 Compound QIAN Bo-zhang二氧化碳（CO2）是石油和天然气等物质燃烧释放出来的一种气体，既是环境温室效应的“元凶”，又是潜在的碳资源。环境友好材料是指在原料采集、产品制造、使用、再生循环利用以及废料处理等环节中对环境负荷小的材料，具有资源和能源消耗少、对生态和环境污染小、再生利用率高的特点。而目前国内外在研发领域具有创新优势的可降解塑料原料二氧化碳基聚合物，则是值得石化行业关注的环境友好型塑料原料。普通的塑料如聚乙烯、聚丙烯等聚合物，是以烃为单体聚合而成，而二氧化碳基聚合物则是以

3、烃和二氧化碳为原料共聚而成，其中二氧化碳含量占31%50%，与常规聚合物相比，对烃及上游原料石油的消耗大大减少。二氧化碳基聚合物不但可以减少石油的消耗，而且其环境适应性也很理想。1 世界研发现状与进展根据IEA统计，2007年中国的二氧化碳排放量已经达60.7亿吨，而同期美国的排放量为57.7亿吨，中国事实上已经成为世界第一碳排放大国。鉴于温室气体排放带来的潜在威胁，全球多数国家已经加入到了努力减少温室气体排放（特别是二氧化碳）的行列中。二氧化碳的回收利用成为当前的热点。二氧化碳基聚合物使用后产生的塑料废弃物，可以通过回收利用、焚烧和填埋等多种方式处理，废弃的二氧化碳基聚合物可以像普通塑料一样

4、回收后进行再利用；进行焚烧处理时只生成二氧化碳和水，不产生烟雾，不会造成二次污染；进行填埋处理时，可在数月内降解。二氧化碳可降解塑料属完全生物降解塑料类，可在自然环境中完全降解，可用于一次性包装材料、餐具、保鲜材料、一次性医用材料、地膜等方面。二氧化碳可降解塑料作为环保产品和高科技产品，正成为当今世界瞩目的研究开发热点。利用此技术生产的降解塑料，不仅将工业废气二氧化碳制成了对环境友好的可降解塑料，而且避免了传统塑料产品对环境的二次污染。它的二氧化碳(r yng hu tn)合成可降解塑料的现状与前景钱伯章二氧化碳是石油和天然气等物质燃烧(rnsho)释放出来的一种气体，既是环境温室效应的元凶，

5、又是潜在(qinzi)的碳资源。环境友好材料是指在原料采集、产品制造、使用或者再生循环利用以及废料处理等环节中对环境负荷最小的材料，具有资源和能源消耗少、对生态和环境污染小、再生利用率高的特点。而目前国内外在研发领域具有创新优势的可降解塑料原料二氧化碳基聚合物，是一种环境友好型塑料原料。二氧化碳基聚合物则是以烃和二氧化碳为原料共聚而成，其中二氧化碳含量占31%50%。，与常规聚合物相比，对烃类及上游原料石油的消耗大大减少。二氧化碳基聚合物不但可以减少对石油的消耗，而且环境适应性也很理想。由二氧化碳制备完全降解塑料的研究始于1969年。日本油封公司发现，二氧化碳和环氧丙烷在催化剂作用下共聚可得到

6、交替型脂肪族聚碳酸酯。这种聚合物具有良好的环境可降解性。美国在此基础上通过改进催化剂，于1994 年生产出二氧化碳可降解共聚物。国外开展该项工作的研究单位主要有二氧化碳基聚合物具有发展潜力金书文普通的塑料原料, 如聚乙烯、聚丙烯等聚合物是以烃为单体聚合而成, 而二氧化碳基聚合物则是以烃和二氧化碳为原料共聚而成, 其中二氧化碳含量占 31%50%, 与常规聚合物相比, 对烃及上游原料石油的消耗大大减少。二氧化碳基聚合物不但可以减少对石油的消耗, 而且环境适应性也很理想。二氧化碳基聚合物是以二氧化碳和烃为原料共聚而成的新型塑料原料。其中二氧化碳含量占 31%50%, 可大大降低对烃的上游原料石油的

7、消耗。目前已批量生产的二氧化碳基塑料原料主要有二氧化碳 / 环氧丙烷共聚物、二氧化碳 / 环氧丙烷 /环氧乙烷三元共聚物、二氧化碳 / 环氧丙烷 / 环氧环己烷三元共聚物等品种。二氧化碳基聚合物使用后产生的塑料废弃物,可以通过回收利用、焚烧和填埋等多种方式处理, 废弃的二氧化碳基聚合物可以像普通塑料一样回收后进行再利用; 进行焚烧处理时只生成二氧化碳和水,不产生烟雾, 不会造成二次污染; 进行填埋处理时,可在数月内降解。二氧化碳降解塑料属完全生物降解塑料类, 可在自然环境中完全降解, 可用于一次性包装材料、餐具、保鲜材料、一次性医用材料、地膜等方面。二氧化碳降解塑料作为环保产品和高科技产品,

8、正成为当今世界瞩目的研究开发热点。利用此技术生产的降解塑料, 不仅将工业废气二氧化碳制成了对环境友好的可降解塑料, 而且避免了传统塑料产品对环境的二次污染。它的发展, 不但扩大了塑料的功能, 而且在一定程度上对日益枯竭的石油资源是一个补充。因此, 二氧化碳降解塑料的生产和应用, 无论从环境保护或是从资源再生利用角度看, 都具有重要的意义。作为节能环保型塑料原料, 二氧化碳基聚合物具有良好的发展前景, 而目前我国在二氧化碳基聚合物研发领域的绝对优势, 也为其产业化发展提供了良机。中科院广州化学公司完成二氧化碳的共聚及其利用二氧化碳高效合成可降解塑料的研究, 该项目的中试成果已转让给广州广重企业集

9、团公司,共同进行二氧化碳可降解塑料 5 000 t/a 工业化试验。该项目在催化剂方面, 创新性地制备了具有自主知识产权的多种担载羧酸锌类催化剂。该催化体系成本低、使用安全、制备简单, 适合工业化规模生产应用。2001 年中科院长春应化所着手(zhushu)进行二氧化碳的固定及利用的工业化研发工作, 与蒙西高新技术(o xn j sh)集团公司合作, 经过(jnggu) 3 年攻关, 建成了世界上第一条3 000 t/“a二氧化碳基全降解塑料母粒”工业示范生产线, 2004 年通过中国科学院高技术研究与发展局组织的专家验收。国内首套二氧化碳降解塑料工业化生产装置于 2004 年初由内蒙古蒙西高

10、新技术集团建成。该工程由内蒙古轻化工业设计院设计, 采用中科院长春应用化学研究所技术, 生产规模大约为3 000 t/a。据称其产品可望部分取代聚偏氟乙烯、聚氯乙烯等医用和食品包装材料, 并可用于一次性食品和药物包装。根据蒙西集团提供的技术数据, 目前已批量生产的二氧化碳基塑料母粒主要有二氧化碳/ 环氧丙烷共聚物、二氧化碳 / 环氧丙烷 / 环氧乙烷三元共聚物、二氧化碳 / 环氧丙烷 / 环氧环己烷三元共聚物等 3 个品种。在强制性堆肥条件下, 560 d内可完全分解。从水泥窑尾气中提取二氧化碳( CO2) , 通过一系列工艺将其制备成食品级纯净度, 再作为原料用于全降解塑料生产, 这项具有独

11、立知识产权, 国内首创的全生物降解二氧化碳共聚物技术, 已由内蒙古蒙西高新技术集团开发成功并投入实际应用。用此技术建立的年产 3 000 t 全生物降解二氧化碳共聚物二氧化碳基聚合物具有发展潜力。二氧化碳为原料合成水性聚氨酯材料廖 玉，李会宁，曹德榕（华南理工大学化学与化工学院，广州 510640；广州千江油漆化学有限公司，广州 510890）摘 要：当今低碳经济发展的一项重要内容就是以二氧化碳为原料合成可生物降解的环保化 合物，主要包括：1环碳酸酯，通过它与胺类固化剂反应合成非异氰酸酯聚氨酯（NIPU）；聚碳酸酯多元醇，通过它与 官能团反应合成聚氨酯材料主要对NIPU的整个合成反应过程机理改

12、性其水性化进行了讨论分析，概述了其特性优势研究前景应用范围和发展现状。关键词：二氧化碳；水性聚氨酯；非异氰酸酯聚氨酯；环碳酸酯；胺类低聚物；氨基硅氧烷；丙烯酸树脂中图分类号：TQ633 文献标识码：A 文章编号：1007-9548（2010）11-0024-06专利(zhunl)：发明名称 - 一种等离子体(dnglzt)活化二氧化碳制备二甲醚的方法申请号CN201210543522申请日2012.12.14公开（公告）号CN103012075A公开（公告）日2013.04.03IPC分类号C07C43/04; C07C41/01; C01B31/18; C07C1/12; C07C9/04申

13、请（专利权）人广西大学;发明人秦祖赠;刘瑞雯;苏通明;范闽光;刘自力;优先权号优先权日申请人地址广西壮族自治区南宁市大学东路100号;申请人邮编530004;本发明公开了一种等离子体活化二氧化碳制备二甲醚的方法，该方法是以二氧化碳为原料，CO2通过一个电压为514kV，频率为0.0512kHz的介质阻挡放电等离子体活化装置，然后以Cu-Fe-Zr/HZSM-5等为催化剂，在原料气为CO2/H2(体积比)=1215的混合气，反应空速为10005000h-1，反应压力为25MPa，反应温度为220280等条件下在一带温度控制的固定床反应器中进行气固相催化反应，反应主要产物为二甲醚，副产甲烷、一氧化

14、碳等。本发明的优点是：工艺简单，操作简单，反应速率快，CO2的转化率较高，反应过程绿色化，且二甲醚的选择性和收率均较高。权利要求书1.一种等离子体活化二氧化碳制备二甲醚的方法，其特征在于，以CO2为原料，采用等离子体活化CO2后，进行催化加氢合成二甲醚，操作步骤如 下：1）等离子体活化CO2：CO2通过一个电压为514kV，频率为112kHz的介质阻挡放电等离 子体活化装置，该装置的一个电极为针电极，另一电极为带孔的平板电极， CO2通过针电极后在针板电极间形成的介质阻挡放电等离子体区被活化，然 后进入固定床反应器进行反应，得到被活化的CO2；2）CO2催化加氢为二甲醚：被活化的CO2进入固定

15、床反应器后，以Cu-Fe-Zr/HZSM-5为催化剂，按 体积比CO2/H2=1215的比例通入氢气，在反应空速为10005000h-1， 反应压力为25MPa，反应温度为220280等条件下进行气固相催化反 应，反应主要产物为二甲醚，副产甲烷、一氧化碳。2.根据权利要求1所述的等离子体活化二氧化碳制备二甲醚的方法，其 特征在于，CO2在反应前经过一个等离子体活化过程。3.根据权利要求1所述的等离子体活化二氧化碳制备二甲醚的方法，其 特征在于，所述步骤1）等离子体活化CO2：其中CO2通过一个电压为14kV， 频率为12kHz的介质阻挡放电等离子体活化装置。发明名称 - 电极活化二氧化碳(r

16、yng hu tn)诱导合成碳酸二甲酯的方法申请号CN201110309443申请日2011.10.13公开（公告）号CN102417456A公开（公告）日2012.04.18IPC分类号C07C68/04; C07C69/96申请（专利权）人刘洋;发明人刘洋;优先权号优先权日申请人地址北京市海淀区中关村南大街5号北京理工大学附小6(3)班学生;申请人邮编100081;本发明涉及电极活化二氧化碳诱导合成碳酸二甲酯的方法，以二氧化碳为原料用电解法活化诱导二氧化碳合成碳酸二甲酯的技术方法，具体涉及二氧化碳的利用(lyng)与环境保护，属于新型能源材料与电化学合成领域。熔二氧化碳溶解于一固碳溶液中，

17、用电解的方式使二氧化碳在固碳溶液中的铜电极上进行电化学活化，再与甲醇反应制备碳酸二甲酯；固碳溶液由乙腈和四乙基溴化铵组成；其中，乙腈为溶剂，四乙基溴化铵为活性剂；固碳溶液的制备方法是：将乙腈、四乙基溴化铵投料于带搅拌的容器中，开启搅拌直至四乙基溴化铵完全溶于乙腈之中，制备完毕备用。本发明具有环保、无毒、试验设备要求低的特点；无需高温(gown)和高压条件。权利要求书1.电极活化二氧化碳诱导合成碳酸二甲酯的方法，其特征在于具体步骤为：1)将铜、镁两个电极及惰性气体导管和二氧化碳进料管分别固定在电解池 上，通入氮气或氦气，直至赶尽电解池中的空气；2)向步骤1)中的电解池中加入固碳溶液；3)向固碳溶

18、液中缓慢通入二氧化碳气体，通入二氧化碳气体的质量为固碳 溶液质量的5080，使溶液置于二氧化碳氛围；开启电解电源，控制电压为 1.812V之间，电流在0.0110A之间，进行电解反应550min；在电解反应的 全过程中二氧化碳气体一直保持通入状态；4)电解结束后，将电解活化反应的液体转移至单口回流瓶中，并向回流瓶 中加入甲醇，加入的甲醇与二氧化碳的摩尔比为10.30.6，用碘甲烷作诱导剂， 碘甲烷的加入量为液体质量的0.0050.01，在4270回流60500分钟； 回流结束后，冷却至室温后，将溶液倒入分液漏斗中，用蒸馏水反复洗涤，精 制直至洗涤至无卤离子为止，以无水硫酯镁干燥，得到碳酸二甲酯

19、产物；上述 反应二氧化碳为过量，以甲醇的质量计，转化率在98以上。2.根据权利要求1所述的电极活化二氧化碳诱导合成碳酸二甲酯的方法， 其特征在于：步骤2)中固碳溶液由乙腈和四乙基溴化铵组成；其中，乙腈为溶 剂，四乙基溴化铵为活性剂，以固碳溶液的总质量计，乙腈占固碳溶液的89 98.8，四乙基溴化铵占1.211。3.根据权利要求1所述的电极活化二氧化碳诱导合成碳酸二甲酯的方法， 其特征在于：固碳溶液的制备方法是：将乙腈、四乙基溴化铵投料于带搅拌的 容器中，开启搅拌直至四乙基溴化铵完全溶于乙腈之中。Elsevier：Progress in Organic Coatings 51 (2004) 25

20、7266An approach to the dry-state preparation of coating particlesfor use in dry surface treatment of paperKaisa Putkistoa, Juha Maijalaa, Johan Gronb, Mikael Rigdahlca Tampere University of Technology, Paper Machine Automation, P.O. Box 692, FIN-33101 Tampere, Finlandb Metso Paper Inc., Technology,

21、Wartsilankatu 100, FIN-04400 Jarvenpaa, Finlandc Department of Materials Science and Engineering, Chalmers University of Technology, SE-41296 Gothenburg, SwedenReceived 17 March 2004; accepted 5 July 2004AbstractDesired savings in energy, raw materials and processing in the manufacture of coated pap

22、ers may lead to the development of processeswith reduced usage of water. One proposed process, the dry surface treatment (DST) for pigment-coating of paper has been studied in alaboratory scale. The treatment involves the application of dry, powdery coating materials on the paper surface and fixatio

23、n of the depositedlayer in a thermomechanical compression and smoothening phase in a heated roll nip. Electrostatic deposition of charged particles enables a non-contact coating application.In the previous studies, the DST-papers produced with two or multi-component powdery materials, that were form

24、ed by drying coating suspensions, exhibited coating coverage, surface strength and smoothness similar to commercial coated mechanical reference papers at equal coat weights, but a generally larger pore size of the dry-formed coatings gave higher levels of oil absorption, air permeability and somewha

25、t irregular ink setting properties. This study aims to explore the possibilities to prepare the DST coating particles in a dry state. The eventual target is to obtain coating particles in the size range used in conventional pigment coating and adjust the binder properties, content and distribution i

26、n a favourable way with regard to the structure of the coating layer. Synthesis of particulate polymers under water-free conditions in supercritical carbon dioxide is described and performed. Hybrid coating particles, consisting of the pigment and binder together, were prepared and evaluated for the

27、ir structure and the coating applicability. 2004 Elsevier B.V. All rights reserved.Keywords: Dry surface treatment; Electrostatic deposition; Supercritical carbon dioxide; Dispersion polymerisation; Hybrid particle; Coating structure1. IntroductionThe dry surface treatment (DST) of paper-based subst

28、rates involves application of dry, powdered coating materials on the paper surface and fixation of the deposited layer in an immediate thermomechanical compression and smoothening phase 1. Electrostatic deposition of charged coating particles allows coating application without contacting the web. Th

29、e thermoplastic binders of the coating soften and deform in the fixing phase in order to bond the pigment particles together and anchor the coating layer to the fibrous substrate2,3. The advantage derives from an integrated dry process,i.e. the preparation and processing of coating materials in dry

30、form. Compared to the conventional coating color preparation and the drying of the wet-coated web, the DST process could reduce the energy requirement of papermaking. In addition, by eliminating the rewetting and drying cycle of the paper, the negative effects of water on the quality of the paper co

31、uld be avoided or reduced.With conventionally suspended materials, the advantage is the rather uniform composition and fine particle size in water, but the drying in order to form coating particles increases the costs of operation as well as induce a risk for aggregation of particles 2, which in sev

32、ere cases may impair the properties of the DST coating layer(Fig. 1).Journal of Colloid and Interface ScienceOne-pot preparation of thermoresponsive silica-poly(N-isopropylacrylamide)nanocomposite particles in supercritical carbon dioxideChengwei Wang, Jing Wang, Wei Gao, Jiqing Jiao, Huajie Feng, X

33、in Liu, Liuping Chen *School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, Guangdong 510275, Peoples Republic of Chinaa b s t r a c tInorganic/polymer nanocomposite silica-poly(N-isopropylacrylamide) (SiO2-PNIPA) was successfully synthesized through a one-pot approach in

34、supercritical carbon dioxide (scCO2). All raw materials, N-isopropylacrylamide(NIPA), vinyltriethoxysilane (VTEO), tetraethoxysilane (TEOS), initiator 2,20-azobisisobutyronitrile(AIBN), crosslinker N,N0-methylenebisacrylamide (MBAM) and hydrolysis agent acetic acid (AA) were introduced into one auto

35、clave and the parallel reactions of free radical polymerization and hydrolysis/condensation occurred simultaneously in the reaction mixture with scCO2 as solvent. The obtained novel composite particles were characterized by Fourier transform infrared spectroscopy(FTIR), scanning electronic microscop

36、y (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). The swelling ratios (SR) and lower critical solution temperatures(LCSTs) of the prepared thermoresponsive microspheres were investigated by swelling tests and ultravioletvisible (UV) spectrophotometry, re

37、spectively. TEM images demonstrated that well-dispersed particles with diameter less than 100 nm were formed. The composite microgels exhibited higher LCSTs than poly(N-isopropylacrylamide) (PNIPA) microgels did. The in vitro release simulation of the particles in situ impregnated with ibuprofen ind

38、icated that SiO2-PNIPA composites could improve the drug releasing effect of the microgels as controlled drug delivery systems._ 2009 Elsevier Inc. All rights reserved.1. IntroductionStimuli-responsive polymers are synthetic functional polymers that respond in some desired way to a change in tempera

39、ture, pH,electric or magnetic field, or some other parameter 1. The namesmart polymer is coined based on its similarity to biopolymers2. Stimuli-responsive polymers have been studied as smart or intelligent materials to be applied in biomedical fields and chemomechanical devices 3,4. Poly(N-isopropy

40、lacrylamide) (PNIPA), one of the most widely studied temperature-responsive polymers, exhibits a transition from a hydrophilic state to a hydrophobic state at a temperature known as the lower critical solution temperature (LCST) 5. The coil-globule transition based on hydrationdehydration behavior i

41、s triggered by temperature changes 6,7.Polymer composite materials have aroused extensive exploitation interest in recent decades 812. Hybrid composites with organic and inorganic moieties mixed on a molecular scale may achieve a synergetic combination of the properties that cannot be obtained from

42、each of the components 13. Recently, a new class of polymeric materials which combine the unique physical properties of inorganic particles with the processability and flexiflexi bility of organic polymer matrix has been investigated extensively 1418. The unique properties of siloxane polymers, aris

43、ing mainly from the physical and chemical characteristics of siloxane bonds, have led to their widespread applications in many diversefields 19,20.Carbon dioxide is non-flammable, relatively non-toxic and naturally abundant. Consequently it has been promoted as a sustainable solvent in chemical proc

44、essing. The green properties of carbon dioxide have provided the driving force to develop many new applications 2128. Charpentier et al. presented a novel approach to obtain silica-poly(vinyl acetate) nanocomposites using FTIR spectroscopy to analyze the free radical polymerization and hydrolysis pr

45、ocess in scCO2. The changes of the characteristic groups in the two parallel reactions were thoroughly monitored through in situ ATR-FT-IR analysis 29. However, little information about the properties of the prepared products was presented. In this paper, the one-pot synthesis of SiO2-PNIPA polymer

46、composites was carried out by combining the free radical polymerization of vinyl monomers and the hydrolysis/condensation of siloxanes. The effects of initiator, crosslinker and reaction process parameters on the morphologies and properties of the composite particles were comprehensively investigate

47、d. The detailed microstructureand microgel behavior of the SiO2-PNIPA polymer composites and the release effect of the prepared ibuprofenimpregnated drug delivery systems were presented.Journal of CO2 UtilizationRecent advances in carbon dioxide based copolymers Yusheng Qin, Xingfeng Sheng, Shunjie

48、Liu, Guanjie Ren, Xianhong Wang*, Fosong Wang Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR ChinaA B S T R A C T Carbon dioxide is becoming increasingly important synthetic feedstock for chemicals and materials, si

49、nce it is abundant, low-cost, non-toxic. One growing area in CO2 chemistry utilization is the development of catalysts for the polymerization of CO2 and epoxides to prepare CO2 based copolymers, including high molecular weight aliphatic polycarbonates and low molecular weight poly(carbonate- ether)

50、polyols. Among all the aliphatic polycarbonates, poly(propylene carbonate) (PPC) has the best opportunity for scale-up commercialization. PPC is not only cheap since it contains over 40 wt% CO2, but it also exhibits good biodegradability, which has wide application in throw-away packaging materials,

51、 or even gas barrier films. Poly(carbonate-ether) polyols are low-molecular weight polyether carbonates with terminating hydroxyl groups, which are potential large scale raw materials in polyurethane industry. Herein, the recent progress of the CO2 based polymers will be highlighted, and the future

52、in this area will be discussed. _ 2014 Published by Elsevier Ltd.Carbon dioxide is the waste gas from combustion of fossil resources, chemical processes or grain fermentation, it is therefore abundant and low-cost. As far as chemical utilization of CO2 is concerned, its thermodynamic stability signi

53、ficantly limits its use as an active reagent in synthetic chemistry. To overcome this limitation, reactions employing CO2 with highly reactive reagents have been explored using metal catalysts. The catalytic coupling of CO2 with heterocyclic compounds has received considerable attention, especially

54、the copolymerization of CO2 with epoxides to polycarbonates 15. In the past four decades, epoxides including propylene oxide (PO), cyclohexene oxide (CHO) and epichlorohydrin (ECH) have been used to copolymerization with CO2. Among these, poly(propylene carbonate) (PPC), the alternat-ing copolymer o

55、f PO and CO2, has received the most attention both in industry and academic research as one of the emerging low-cost and eco-friendly polymer materials 3,4. In particular, the commercialization of PPC is currently being initiated in several countries, especially in China. In general, the products of

56、 the copolymerization of PO and CO2 fall into two categories according to the utilization, one is PPC with high molecular weight and high carbonate contents exhibiting good biodegradability, which has wide application in packaging materials, or even gas barrier films. The other is polycarbonate poly

57、ols with low molecular weight as raw material for polyurethane industry. In the past decade, historical development in this area has been comprehensivelyreviewed in the literature 1,4,69. Herein, we will summarize the latest progress in synthesis, modification and applications of high molecular weig

58、ht CO2 based polycarbonates, and the progress in low molecular weight polymer polyols will also be discussed. 1. Environmental friendly catalysts Since the pioneer work of Inoue 10,11, various types of catalysts including heterogeneous and homogeneous metal com-plexes have been developed. Typical he

59、terogeneous catalysts include ZnEt2-active hydrogen containing compound systems 1113, zinc dicarboxylates 1418, double metal cyanide complexes 1926, and rare-earth metal coordination ternary catalysts 2731, though the chemical structures or crystal structures of heterogeneous catalysts are not clear

60、, they are convenient in synthesis and handling, showing more potentiality for industrial purpose. Homogeneous catalyst is interesting for academic research, Inoue developed the first single-site homogeneous catalyst, metal tetraphenylporphyrin complex, for epoxide-CO2 copolymerization 32. Later hom