新型水溶性超支化聚酰胺-酯的合成

均苯四甲酸酐与二乙醇胺经酰化反应制得中心核(4);4与AB2单体2,2-二羟甲基丙酸经熔融缩聚合成了一种新型水溶性的二代超支化聚酰胺-酯(1),其结构与性能经FT-IR,GPC,粘度法,化学滴定等表征。4的Mn=1 683,Mw=1 911,Mw/Mn=1.14,[ηinh]=0.067 6 dL·g-1;1的Mn=3 750,Mw=4 904,Mw/Mn=1.31,[ηinh]=0.086 1 dL·g-1。     

超支化聚酰胺-酯单体的常温快速合成

以取代马来酸酐和二乙醇胺为原料,在常温下快速(2 h)合成了一系列的超支化聚酰胺-酯AB:单体,其结构经FT-IR表征.用中和滴定法跟踪测定反应体系的酸值,根据酸值与反应进度的关系,讨论了快速合成的意义.提出了可能的反应机理.     

超支化聚甲基丙烯酸甲酯的制备及其流变性能

甲基丙烯酸羟乙酯与S-1-十二烷基-S’-(α,α’-二甲基-α″-乙酸)三硫代碳酸酯通过酯化反应合成了带有甲基丙烯酸酯双键的可聚合RAFT试剂——S-1-十二烷基-S’-(α,α’-二甲基-α″-甲基丙烯酰氧基乙酸乙酯)三硫代碳酸酯(3);3与甲基丙烯酸甲酯共聚合成了不同支化度的支化聚甲基丙烯酸甲酯[4-x(x=1,3,5,7,10)],其结构经1H NMR和IR表征。对4-x的熔体流变特性进行了研究。结果表明,4-x的分子量和分布得到了有效控制。支化结构不仅有效降低了4-x的黏度,也使熔体的剪切稀化行为变得不显著,并且4-10还表现出两次剪切稀化行为。     

单体慢加入技术对超支化聚合物分子参数的影响

详细分析了单体慢加入到多官能度核分子中制备超支化聚合物的动力学过程,以单体转化率为参数导出了产物的聚合度分布函数、平均聚合度、多分散性指标和支化度等分子参数的解析式,计算结果与文献报道的实验数据十分一致.分子参数依赖于核的官能度(f)、核分数(α)和单体转化率(x),这为通过聚合反应条件来进行分子结构的设计提供了理论依据.与一步聚合方法的产物相比,单体慢加入技术能够改进产物的分子量分布,提高其支化度.     

光固化聚氨酯丙烯酸酯涂层的固化动力学及其光稳定化研究

研究了脂肪族和芳香族聚氨酯丙烯酸酯类低聚物的光固化动力学和反应型受阻胺 ( r HALS)对光固化聚氨酯丙烯酸酯涂层的光防护效果。加速老化实验结果表明 :r HALS的光稳定体系可有效地将试样的黄度指数 (YI)控制在较低水平内 (辐照时间 10 0 0h ,YI <1%～ 2 % )。含有 r HALS的光固化涂层比相应的商品HALS具有更优越的耐光氧老化性能。     

超支化聚酰胺酯改性聚甲基丙烯酸甲酯微流控芯片的制备及其在生物分子分离检测中的应用

利用亲水性超支化聚酰胺酯通过化学键合的方法对聚甲基丙烯酸甲酯(PMMA)微流控芯片的表面进行改性。对改性后PMMA微流控芯片的表面进行了接触角的测定,利用扫描电子显微镜(SEM)和体视显微镜观察了改性后芯片的表面形貌。结果表明,改性后的PMMA微流控芯片表面形成了一层均匀、致密、连续的亲水性涂层,芯片表面的亲水性得到了明显提高,接触角由未改性时的89.9°降低到29.5°。改性后芯片的电渗流较之改性前明显降低。利用芯片对腺苷和L-赖氨酸两种生物分子进行了分离检测。两种生物分子实现了完全分离,所得到的检测峰峰形尖锐,分离清晰。对腺苷和L-赖氨酸的分离柱效(理论塔板数)分别高达8.44×104 塔板/m和9.82×104 塔板/m,分离度(Rs)达到5.31,均远远高于未改性的芯片。改性后的芯片具有良好的分离时间重现性。本研究为提高PMMA微流控芯片的亲水性和应用范围提供了一种新的有效方法。     

海藻酸钠改性超支化聚酰胺对重金属离子的选择性吸附性能

采用共价键结合法,利用戊二醛,将海藻酸钠与端氨基超支化聚酰胺进行共价交联,制备出海藻酸钠改性超支化聚酰胺吸附材料,通过FT-IR对其结构进行表征,并考察了海藻酸钠改性超支化聚酰胺对水体中Pb²⁺、Cd²⁺和Zn²⁺的吸附行为。研究结果表明,海藻酸钠改性超支化聚酰胺对Pb²⁺、Cd²⁺和Zn²⁺的饱和吸附能力分别为210.56 mg·g^-1、130.53 mg·g^-1和129.11 mg·g^-1,且符合Langmuir等温吸附模型,可见海藻酸钠改性超支化聚酰胺对Pb²⁺有明显的吸附选择性;而多元混合体系中的吸附实验表明,Cd²⁺或Zn²⁺与Pb²⁺的共存可以对Pb²⁺的吸附产生协同促进作用,而Pb²⁺对共存重金属离子的吸附则是明显拮抗作用,二元混合体系中Pb     

无光敏剂光引发亲水性单体在嵌段聚醚氨酯膜上接枝聚合的研究

<正> 嵌段聚醚氨酯(SPEU)是一类应用广泛的医用高分子材料。用亲水性单体进行表面接枝改性,已有不少研究,接枝聚合方法有铈盐引发、辐射引发以及光敏引发等。 本文研究一种新的接枝方法,不加光敏剂,用紫外光照射,直接引发亲水性单体接枝于SPEU膜上、接枝的单体有丙烯酰胺(AAM)与N,N-二甲基丙烯酰胺(DMAA),从接枝前后膜的性能变化可以证实接枝反应的发生。文中研究了反应条件与单体结构对接枝率的影响,并通过模型化合物,对接枝部位进行了研究。     

在四官能团引发剂存在下的自缩合乙烯基聚合反应制备丙烯酸酯类超支化共聚物

超支化聚合物具有特殊的结构和性能 ,可通过一步法聚合直接制得 ,具有大规模工业应用前景 .近年来 ,超支化聚合物的研究已成为高分子科学的热门课题之一[1～ 3 ] .超支化聚合物的一个主要缺点是它的分子量分布比较宽 .Ｍ櫣ｌｌｅｒ[4] 等通过理论计算指出 ,在聚合体系中加入ｆ个功能基团的分子Ｂｆ[对自缩合乙烯基聚合反应 (ＳＣＶＰ) ,Ｂｆ为ｆ个引发基的引发剂 ;对ＡＢｘ 型单体的缩聚反应 ,为有ｆ个Ｂ官能团的分子 ],可以降低超支化聚合物的分子量分布 ,这一结果已被实验证实[5～ 7] .我们用ＭｏｎｔｅＣａｒｌｏ方法模拟了在多官能团引…     

紫外光固化超支化聚硅氧烷的合成及其光固化动力学研究

利用γ-甲基丙烯酰氧基丙基三甲基硅氧烷的受控水解反应即A2-B3单体对法来制备超支化聚硅氧烷,并对合成出的聚合物通过FT-IR、1H-NMR和多角度激光光散射技术(MALLS)进行了表征.结果表明,所得聚合物具有超支化结构且分子中含有大量活性官能团,从而可以实现紫外光引发固化.通过等温差示光量热实验(DPC)研究了聚合物结构、引发剂用量、光强度和聚合温度对聚合物光固化行为的影响规律,并得到了其中一种聚合物的光固化动力学参数,光固化反应总级数约为3,表观活化能为16.9kJ/mol.     

Photopolymerization of Dendritic Acrylated Aromatic/Aliphatic Polyesters and Properties of Their Cured Films

Introduction　　 Radiation( UV/EB) curing technology iswidely used for the preparation of curablematerials,such as inks,coatings and compositesdue to their high cure rate,environmentalprotection,and the saving of energy[1～ 3 ] .For theprocessing of resins as the application,two basicparameters are the most important,namely,theresulting degree of conversion of functional groupsand the polymerization kinetics during the curing,which determine the value for its intended end use.　　 The dendri…     

预氧化聚铝碳硅烷纤维的热分解动力学及其机理

利用热重分析仪(TGA)对预氧化聚铝碳硅烷(PACS)纤维进行了热动力学研究, 用改良的Coats-Redfern法计算了动力学参数, 用Doyle法计算了理论失重值, 并根据FT-IR, XRD和SEM对其热分解的机理进行了分析. 结果表明, 在热分解反应的主要阶段, 预氧化纤维的反应活化能低于PACS纤维, 氧的引入有利于纤维的热分解; 快速升温有利于预氧化PACS纤维的热分解. 在初始分解阶段, 主要为低分子量的PACS和H₂O的逸出, 同时≡Si—H键之间以及≡Si—H与≡Si—CH₃键发生了脱氢、脱CH₄反应, 从而导致交联程度的增加; 随热分解温度进一步的提高, 分子的有机侧基急剧热解, 分解产物从有机物转变为存在部分微晶的无机结构; 热分解温度继续提高, 纤维结构进一步完善, 1300 ℃左右, β-SiC晶粒大小约为2～4 nm左右, 纤维具有较好的性能.     

Photo and Thermal Cured Silicon‐Containing Diethynylbenzene Fibers via Melt Electrospinning with Enhanced Thermal Stability

An inorganic–organic hybrid material, poly(dimethylsilylene ethynylenephenyleneethynylene) (PMSEPE), was synthesized in a mild condition and its microfiber was successfully produced by melt electrospinning. The electrospinning parameters, which affected the morphology and diameter of fibers, were well investigated. To maintain the fiber structure at thermal cured temperature (above melting point), the PMSEPE fibers were enhanced via thiol‐yne photo polymerization. Followed by the thermal curing reaction, the heat‐resistance and mechanical properties of fibers were enhanced. The mechanism of two‐step curing was explored and confirmed by means of Fourier transform infrared, differential scanning calorimetry, and X‐ray photoelectron spectroscopy (XPS). Thermaogravimetric analysis and scanning electron microscopy results show that after carbonization at 800 °C, the two‐step cured fibers had only a small weight loss (20%) and the fibers can still maintain the original morphology. Moreover, the two‐step cured fiber exhibited a high tensile strength (55.4 MPa) and a small elongation at break (0.02%). All the results indicate that the fibers could be applied as fiber‐reinforced materials. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2815–2823     

紫外光固化PDLC膜性能的温度效应

考察了紫外光固化PDLC膜的电光性能及其温度依赖性,阐述了其作为显示器件的工作稳定性。指出确定PDLC工作温度范围的方法,对PDLC膜中液晶相的N-I转变行为及其与膜的内部结构的关系进行了讨论。     

纳米金属氧化物隔热窗膜及性能研究

本文研究了UV固化纳米金属氧化物(ATO)粒径和涂布厚度与薄膜隔热性能的关系,比较了纳米涂层隔热膜与磁控溅射隔热膜的性能和特点。结果表明,光固化树脂单体等组分的官能度、纳米金属氧化物的用量和纳米材料粒径与涂层的隔热性能有密切关系,合理的材料组合制成的隔热膜隔热率可达到50%以上。两类隔热窗膜的对照测试显示,纳米涂层隔热膜具有高透高隔热和隔热性能稳定的特点,纳米涂层隔热膜湿热老化后红外线透过率变化只有5%左右。     

氮丙啶交联剂的交联性能及固化动力学研究

合成了一种氯丙啶交联剂，并以丙烯酸树脂乳液为模型化合物对交联剂的交联性能及固化动力学进行了研究。结果表明：在丙烯酸树脂乳液中加入适量的氯丙啶交联剂，可使胶膜的力学性能及耐水碱性，耐溶剂性都得到很大的提高；但交联对玻璃化转变温度的影响较小。用程序升温DSC（差示扫描量热法）方法对固化反应动力学进行了研究，计算出固化反应的活化能。     

Thermal Properties of N-ethyl-N-phenyl-Dithiocarbamates and Their Influence on the Kinetics of Cure

The thermal properties (in the temperature range of 100–250°C) of N-ethyl-N-phenyldithiocarbamatecomplexes of Zn(II), Co(III), Ni(II), Cu(II) and Pb(II) and their influence on the kinetics of cure have been studied by differential scanning calorimetry (in nitrogen). It was found that Zn(II), Co(III) and Pb(II) dithiocarbamates melted without further effects, while the melting of Ni(II) and Cu(II) dithiocarbamates is accompanied with decomposition. From the kinetic point of view, the dithiocarbamates decrease the values of the reaction order and the values of rate constants follow this order (with respect to the metal ion): Zn(II)<Cu(II)<Pb(II)<Ni(II)<Co(III).This revised version was published online in November 2005 with corrections to the Cover Date.     

Influence of Reactive Diluent on UV-curing of Acrylate Terminated Hyperbranched Polymers

A Aeries of hydroxylic hyperbranched polymers were derived from 2,2-bis (methylol) propionic acid and tris (methylol) propane reacted with acrylic acid to various extents. The obtained acrylated hyperbranched polymers alone or with a monofunctional diluent, isobornylene acrylate(IBOA) were further cured by UV radiation. The cured films based on the modified polymers alone all demonstrated poor mechanical properties due to their high network densities and low moving ability of polymer chains. For the composite systems, the cured films demonstrated improved mechanical properties due to the low network densities and high chain moving ability. With more IBOA included in the systems, acrylate groups can react to a higher extent during the curing process.     

Synthesis of Perfluorinated Oxetane and Surface Properties of Its Cationic UV Cured Coating as a Reactive Additive

Perfluorinated oxetane(F-OXE) was synthesized via the ring-opening reaction of epoxy-functionalized oxetane with 2-(perfluorooctyl)ethanol under base-catalysis, and characterized by FTIR and ¹H NMR spectroscopy. The synthesized F-OXE was mixed with a commercial cationic UV curable resin, UVR6110, as a reactive additive at different mass fractions, and UV-irradiation cured in the presence of triphenylsulphonium hexafluoroantimonate as a cationic photoinitiator. The surface property study of cured films indicated that both hydrophobicity and oleophobicity were effectively enhanced by the addition of a small amount of F-OXE. The contact angles of water and 1-bromonaphthalene on the surface of the cured film with 1.0%(mass fraction) F-OXE loading increased from 72° to 106° and from 0° to 76°, respectively, compared with those on the surface of the film without F-OXE addition. The surface tension of UVR6110-F-OXE cured film decreased greatly from 55.6 mN/m of referenced film to 22.9 mN/m. The results from X-ray photoelectron spectroscopy analysis confirm the migration and aggregation effect of perfluoroalkyl group to the surface of cured film. For 1%(mass fraction) addition of F-OXE, the relative content of fluorine greatly increased from 0.70%(mass fraction) in the interior of the cured film to 36.73%(mass fraction) at the surface of the cured film, whereas those of carbon and oxygen decreased from 73.29% to 40.96% and from 26.00% to 22.30%, respectively.     

腰果酚的紫外光固化机理和固化膜性能

研究了腰果酚在无光引发剂条件下的紫外光固化反应,并用IR、UV、元素分析、GPC等分析手段分析了腰果酚的紫外光固化机理及其固化膜性能。结果表明:在紫外光辐照下,腰果酚通过侧链发生氧化聚合反应,和酚羟基的邻对位失去质子形成的自由基引起的苯环缩合反应,最终形成体型高聚物。腰果酚的紫外光固化膜的常规物理机械性能、抗溶剂性、耐化学介质腐蚀性、热稳定性和抗紫外线性能均优于腰果酚醛缩聚物(PC)涂膜。