CPDB为链转移试剂的脱氢枞酸基单体的RAFT聚合研究

以脱氢枞酸（β-甲基丙烯酰氧基丙基）酯（DAHPMA）为单体,偶氮二异丁腈（AIBN）为引发剂,2-氰基-2-丙基苯并二硫（CPDB）为链转移试剂,在四氢呋喃溶液中进行可逆加成-断裂转移自由基聚合反应（RAFT）制备得到脱氢枞酸基酯均聚物。动力学研究表明了脱氢枞酸基单体可以在RAFT聚合下具有活性可控的特征,同时探讨了CPDB的浓度对松香基单体的RAFT聚合的影响,发现CPDB的浓度对聚合过程的速率和可控性以及相对分子量和相对分子质量分布都有一定的影响。通过核磁证实了该松香基均聚物的成功合成,接触角测试表明该聚合物具有高疏水性。     

含松香骨架甜菜碱类两性表面活性剂的合成

以脱氢枞酸为原料,合成了3种新型含松香骨架的甜菜碱类表面活性剂:N-(2-脱氢枞酰氧基)乙基-N,N-二甲基羧甲基甜菜碱,N-(2-脱氢枞酰氧基)乙基-N,N-二甲基磺丙基甜菜碱和N-(2-脱氢枞酰氧基)乙基-N,N-二甲基磷酸酯甜菜碱。通过红外和核磁共振氢谱对产物结构进行表征,3种甜菜碱cmc分别为3.16 mmol.L-1、3.01 mmol.L-1和2.56 mmol.L-1,此时表面张力分别为31.91 mN.m-1、33.20 mN.m-1和25.79 mN.m-1,说明3种甜菜碱具有好的表面活性。     

脱氢枞酸(β-丙烯酰氧基乙基)酯的合成和表征

以脱氢枞酸为原料,以草酰氯为酰基化试剂(摩尔比1∶1),先合成脱氢枞酸酰氯,然后再与丙烯酸-β-羟基乙基酯酯化(摩尔比1∶1),合成脱氢枞酸(β-丙烯酰氧基乙基)酯,得率75%,质量分数98.5%。用FTIR、GC-MS、13CNMR和DSC对其结构和性能进行了表征。结果表明,脱氢枞酸(β-丙烯酰氧基乙基)酯是一种熔点为59~61℃的白色晶体,在引发剂的存在下,可以发生聚合反应,均聚物玻璃化转变温度约为54.2℃。     

双亲嵌段共聚物PSt-b-P(St-alt-MA)-b-PAA的自组装行为

以三硫代碳酸二(α, α'-二甲基-α-乙酸)酯(BDATC)为链转移剂, 以苯乙烯、马来酸酐、丙烯酸为原料, 通过可逆加成-断裂链转移(RAFT)合成了双亲嵌段共聚物PSt-b-P(St-alt-MA)-b-PAA。通过选择性溶剂N, N-二甲基甲酰胺(DMF)诱导聚合物进行自组装, 利用紫外-可见光光度仪、纳米激光粒度仪详细研究了共聚物中亲疏水嵌段长度、初始浓度、体系pH值对聚合物自组装行为的影响。通过化学交联的方法制备得到了聚合物交联胶束, 利用透射电镜表征了形貌与尺寸, 研究明确了其形状和尺寸的稳定性。结果表明, 上述因素均会影响共聚物的自组装行为和自组装胶束的形态, 经乙二胺交联得到的交联自组装胶束平均粒径为145.4nm, 并具有良好的形状和尺寸稳定性。     

去氢枞酸基新型甜菜碱类两性表面活性剂的合成

从歧化松香中分离提纯去氢枞酸,然后以去氢枞酸为原料,经去氢枞酸缩水甘油酯及叔胺中间体,合成了N-(3-去氢枞酰氧基-2-羟基)丙基-N,N-二甲基羧甲基甜菜碱和N-(3-去氢枞酰氧基-2-羟基)丙基-N,N-二甲基(2-羟基)磺丙基甜菜碱这两种新型甜菜碱类两性表面活性剂。通过紫外、红外及质谱分析,对目标产物进行了结构表征,并对其表面张力和临界胶束浓度进行了测定。     

可聚合松香基紫外光固化涂层的合成和性能分析

以两种松香基单体———歧化松香(β-丙烯酰氧基乙基)酯(DREA)和丙烯酸松香(β-甲基丙烯酰氧基乙基)酯(AREA)为原料,通过紫外光固化的方式,合成基于松香的涂层,研究松香基单体配比和交联度对涂层硬度和附着力的影响。结果表明,松香基单体固化效率高,有助于提高聚合物涂层的硬度和储存模量(E’),但附着力差。在配方中加入丙烯酸-2-羟基乙基酯(HEA),可以改善涂层的附着力。涂层组成的最佳配比为:DREA 50%,AREA30%,其它辅助成分20%。     

脱氢松香基甜菜碱两性表面活性剂合成与表征

以脱氢枞酸为原料,经3-松香酰氧-2-羟丙基氯及叔胺中间体,合成N-(3-去氢枞酰氧基-2-羟基)丙基-N,N-二甲基(2-羟基)磷酸酯甜菜碱,并分析了产物及与十二烷基硫酸钠(SDS)的复配体系的表面活性.结果表明其临界胶束浓度(CMC)为1.34 mmol/L,此时表面张力为38.69 mN/m.泡沫力为280 mm,泡沫能力稳定,产物乳化力较强.产物与SDS复配后,其界面活性产生较强烈的增效作用,两者摩尔比为1:1时增效作用最显著.     

两亲性嵌段共聚物的合成及其自组装行为

采用原子转移自由基聚合（ATRP）方法合成了两亲性嵌段共聚物PSt-b-PAA。用1H NMR和GPC等手段对活性聚合进行了确认,对嵌段共聚物的结构进行了表征。两亲性嵌段共聚物在离子液体1-丁基-3-甲基咪唑六氟磷酸盐（[BM IM][PF6]）中形成胶束溶液。用透射电子显微镜（TEM）观察聚合物在离子液体中形成胶束的纳米结构。当疏水链长固定时,胶束的自组装形状主要依赖于亲水链的长度。两亲性共聚物在离子液体中可自组装成可控制结构的纳米胶束,这种纳米胶束可应用在很多领域。     

松香基紫外光固化功能单体的合成和表征

松香是一种重要可再生资源,随着石油资源的日益枯竭,将松香改性成聚合物单体重新受到关注.本文以脱氢枞酸为原料,以草酰氯为酰基化试剂(物质的量比1:1),先合成脱氢枞酸酰氯,然后再与甲基烯丙醇酯化(物质的量比1:1),合成脱氢枞酸甲基烯丙基酯,并分别采用了FT-IR、GC-MS、13C-NMR和DSC对其结构和性能进行表征.研究结果表明,所合成的脱氢枞酸烯甲基丙基酯的质量分数为91.36%,熔程为41.24～52.24℃,在引发剂的存在下可以发生聚合反应,可作为光固化树脂应用于涂料中.     

新品研发辑要

反-4-乙基环己烷甲酸的制备；废聚酯非酸催化合成对苯二甲酸二（2-乙基己）酯的研究；活性炭固载三氯化铁非均相催化合成乙酸环己酯；相转移催化法合成4-氯二苯基溴甲烷；可降解聚醚酯酰胺基聚氨酯共聚物的合成及性能表征。     

Reverse micelles of star-block copolymer as nanoreactors for preparation of gold nanoparticles

The star-block copolymers poly(styrene)-block-poly(4-vinylpyridine) ((PS-b-P4VP)₄) are synthesized by two-step atom transfer radical polymerization (ATRP) using pentaerythritol tetrakis (2-bromoisobutyrate) as initiator. The star-block copolymers form reverse micelles in toluene with the P4VP core and the PS shell. The reverse micelles and their complexes with HAuCl₄·3H₂O are investigated by a combination of dynamic laser scattering (DLS) and static laser scattering (SLS) in toluene. Gold nanoparticles are subsequently obtained by reducing the complex micelles with anhydrous hydrazine. The size and morphology of reverse micelles, hybrid micelles and gold nanoparticles are also investigated by transmission electron microscope (TEM). The obtained gold nanoparticles are of small quantum size (ca. 2 nm) and narrow distribution.     

乙二胺后扩链TDI型聚氨酯水分散体的过程

以甲苯二异氰酸酯（TDI）、聚氧化丙烯二醇和二羟甲基丙酸等为主要原料制备了聚氨酯水分散体,研究了水、扩链温度、原料的-NCO/-OH摩尔比及扩链比对乙二胺（EDA）后扩链TDI型聚氨酯水分散体过程的影响。FT-IR测试表明,分散体中的H₂O可通过与聚氨酯中残留异氰酸酯基团（-NCO）的竞争反应影响EDA的后扩链过程。分子量及粒径与zeta电位测试表明,H₂O扩链导致分散体失稳;低扩链比时,H₂O对EDA的后扩链过程影响明显,但高扩链比时,后扩链聚氨酯的分子量降低;扩链温度升高,经EDA后扩链聚氨酯的分子量降低,而分散体粒径增大。当原料的-NCO/-OH摩尔比为1.20、扩链温度为30℃、扩链比为60%时,可有效降低H₂O对EDA后扩链聚氨酯过程的影响。     

Morphology prediction of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) crystal in different solvent systems using modified attachment energy model

In order to theoretically study the growth morphology of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) crystal in different solvent systems, crystal–solvent models were established, and then molecular dynamics (MD) methods were adopted as a means to simulate particle motion. Modified attachment energy (MAE) model was employed to calculate the growth morphology of TKX-50. The simulation results demonstrate that COMPASS force field and RESP charge are suitable for molecular dynamics simulation of TKX-50. The morphologically dominant growth surfaces of TKX-50 in vacuum are (0 2 0), (0 1 1), (1 1 –1), (1 0 0) and (1 2 0), respectively. In water (H₂O) and N, N-dimethylformamide (DMF) solvents, the (1 1 –1) face is the largest in the habit face, the growth rate of (0 2 0) face becomes faster. With the increase of temperature, the aspect ratios of TKX-50 crystal in DMF solvent increase, and the areas of the (1 2 0) faces decrease. In ethylene glycol /H₂O mixed solvent system with volume ratio of 1/1, aspect ratio of TKX-50 is relatively small. In formic acid /H₂O mixed solvents with different volume ratios (1/4, 1/3, 1/2, 1/1 and 2/1), aspect ratio of TKX-50 is relatively small when volume ratio is 1/2.     

Brush-type amphiphilic polystyrene-g-poly(2-(dimethylamino)ethyl methacrylate)) copolymers from ATRP and their self-assembly in selective solvents

A series of well-defined brush-type amphiphilic polystyrene-g-poly(2-(dimethylamino) ethyl methacrylate)) (PS-g-PDMAEMA) copolymers were successfully synthesized via atom transfer radical polymerization (ATRP), using chloromethylated polystyrene (CMPS) as the macroinitiator. The self-assembly behavior of the resulting brush-type copolymers in deionized water and deionized water/acetone (v/v=2/3) mixture was studied by high performance particle sizer (HPPS). The results showed that the Z-average size of the micelles in deionized water increased with the increase of molecular weight of PDMAEMA, and the corresponding size was larger than that in mixed solvent of deionized water and acetone (v/v=2/3). The morphologies of the micelles self-assembled from PS-g-PDMAEMA in selective solvents were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). When the micelles were prepared in water/acetone (v/v=2/3) mixture and cast them on a glass slide at different temperatures (from 50 up to 200 °C), the transformation of the morphologies of aggregates, from needle-like solid to microcubic particles, was observed using SEM.     

蔗糖在DMF-[BMIm]Cl溶剂中催化制备5-HMF

研究了在N,N-二甲基甲酰胺(DMF)-离子液体[BMIm]Cl混合溶剂中将蔗糖高效转化为5-羟甲基糠醛(5-HMF)的反应。运用紫外-可见分光光度计对水解液中5-HMF进行定量分析并计算其收率。考察了CrCl₃·6H₂O、AlCl₃·6H₂O、SnCl₄·5H₂O、FeCl₃、CoCl₂·6H₂O、ZnCl₂、CuCl₂·2H₂O、CaCl₂ 8种催化剂对反应的催化效果,结果表明AlCl₃·6H₂O催化效果最为明显。以AlCl₃·6H₂O为催化剂研究了不同反应条件如时间、温度、溶剂中DMF-[BMIm]Cl质量比、催化剂AlCl₃·6H₂O的用量对5-HMF收率的影响,得到的最佳条件为以0.5mmol蔗糖为反应物,0.4mmol AlCl₃·6H₂O为催化剂,反应时间2h,反应温度120℃,5g质量比为85:15的DMF-[BMIm]Cl混合溶剂,此条件下5-HMF收率最高可达63.4%。研究表明,DMF-[BMIm]Cl混合溶剂体系对蔗糖转化为5-HMF有一定的促进效果,在此溶剂体系中以AlCl₃·6H₂O为催化剂时可以得到较高的5-HMF产率。     

无机相变材料CaCl2·6H2O的过冷特性

CaCl₂·6H₂O作为一种常见的常温无机水合盐相变材料,由于成本低、易获取、蓄热强而受到广泛的关注。按无水CaCl₂与H₂O的质量比为1.027：1制备了CaCl₂·6H₂O,经X射线衍射（XRD）表征其晶体结构;通过添加成核剂SrCl2·6H₂O和Ba（OH）₂对CaCl₂·6H₂O改性,发现两者的联合作用可抑制过冷,10次熔化-冷却循环平均过冷度1.07℃。采用差示扫描量热仪（DSC）测定CaCl₂·6H₂O添加成核剂前后相变潜热,发现潜热由223.54 J·g^-1降至160.41 J·g^-1;为了扩大CaCl₂·6H₂O相变温度的范围,通过添加质量分数分别为5%、10%、15%、20%和25%的MgCl₂·6H₂O,发现相变温度随MgCl₂·6H₂O质量分数的升高呈线性降低,但不宜超过20%;选取CaCl₂·6H₂O-20% MgCl₂·6H₂O二元共晶盐相变储热体系为改性目标,通过添加1% SrCl2·6H₂O和0.5% CMC,过冷度降至0.57℃,相变潜热为141.09 J·g^-1,低于单独组成盐CaCl₂·6H₂O的潜热223.54 J·g^-1和MgCl₂·6H₂O的潜热163.35 J·g^-1。研究表明,CaCl₂·6H₂O作为无机相变材料具有显著的应用价值。     

Betaine·HCl-6EG-nNiCl2·6H2O低共熔离子液体的黏度和电导率

在常压下303~353 K和303~348 K温度范围分别测定了低共熔溶剂盐酸甜菜碱-乙二醇(Betaine·HCl-6EG)中加入不同浓度NiCl₂·6H₂O形成的Betaine·HCl-6EG-nNiCl₂·6H₂O低共熔离子液体的黏度和电导率,研究了温度、NiCl₂·6H₂O浓度对其黏度、电导率的影响规律。结果表明,在所研究的温度和NiCl₂·6H₂O浓度范围内低共熔离子液体Betaine·HCl-6EG-nNiCl₂·6H₂O都具有较低的黏度和良好的导电性。随着温度的升高,黏度减小,电导率增大,温度对黏度的影响更显著;黏度、电导率与温度的关系均可以用Arrhenius经验公式描述,由此计算得到其黏滞活化能和电导活化能。随着NiCl₂·6H₂O浓度的增加,黏滞活化能和电导活化能均会增大;NiCl₂·6H₂O的加入使得离子液体形成尺寸较大的络合离子,导电离子的有效浓度降低、离子半径增大,导致其电导率减小、黏度增大。     

四元体系LiCl-LiBO2-Li2SO4-H2O在298.15K时的相平衡

采用等温溶解平衡法开展了四元体系LiCl-LiBO₂-Li₂SO₄-H₂O在298.15 K时相平衡实验研究,测定体系溶解度和平衡溶液的折光率、密度、pH和电导率。根据实验数据,分别绘制该四元体系的干基图、水图以及相对应的物化性质-组成图。研究结果表明:在该四元体系298.15 K相图中,有2个无变度共饱点分别为相称共饱点(Li₂SO₄·H₂O + LiCl·H₂O + LiBO₂·2H₂O)和不相称共饱点(Li₂SO₄·H₂O + LiBO₂·2H₂O + LiBO₂·8H₂O)、5条溶解度曲线和4个单盐结晶相区(Li₂SO₄·H₂O、LiCl·H₂O、LiBO₂·8H₂O和LiBO₂·2H₂O),无复盐和固溶体产生,属于简单四元体系水合物Ⅱ型相图。实验研究中,发现2种偏硼酸锂水合矿物存在(LiBO₂·8H₂O和LiBO₂·2H₂O),LiCl对Li₂SO₄的盐析效应显著;四元体系平衡溶液物化性质随着溶液中氯化锂浓度的变化呈现规律性的变化。     

Synthesis of reductive responsive polyphosphazenes and their fabrication of nanocarriers for drug delivery application

Reductive responsive nanovehicles have the ability to deliver the anticancer drugs to intracellular compartments. The purpose of this study was to develop reductive sensitive nanocarriers based on polyphosphazenes. Amphiphilic polyphosphazenes with hydrophilic reductive sensitive side group and different molecular weights were synthesized and characterized. The synthesized copolymers show solvent dependent self-aggregation and form spherical micelles by using THF as co-organic solvent in dialysis method with critical micelle concentration value ranging from 5.73 µg/mL to 11.24 µg/mL. Micelles can encapsulate the hydrophobic drugs such as camptothecin (CPT) and indomethacin. In in vitro release experiments, CPT-loaded micelles release 70–80% of the loaded CPT in the presence of reducing agent dithiothreitol within 15 h. The results indicate that these reductive sensitive amphiphilic polyphosphazenes may find an application as anticancer drug carriers for safe drug delivery.     

Solution properties of polyamic acids and their amine salts

Solution properties such as viscosity, critical concentration, radius of gyration, and activation energy in aqueous solutions are described for [BPDA/PDA]polyamic acid (PAA) and their salts with various amines (PAS). Although PAA and their salts with Bu₃N, Hex₃N, Oct₃N, and pyridine, were insoluble in H₂O, only the salt with Et₃N (PAS(Et₃N)) was soluble in H₂O. The different solubility of PAS suggests that higher base strength as well as shorter alkyl length of amines enhance water solubility of PAS. PAS(Et₃N) showed critical concentrations at 18, 14, and 7.8 wt% in NMP, NMP/H₂O (1/1), and H₂O, respectively. The radius of gyration, which is calculated from the critical concentration, in H₂O is 1.3 times larger than that in NMP; that is, the polymer chain expands in H₂O rather than in NMP. PAS(Et₃N) in H₂O showed larger activation energy of viscosity than that in NMP. However, PAA and PAS(Et₃N) showed similar activation energies in the NMP solution. Therefore, it is concluded that the amine salts of the polyamic acids are hydrated by several water molecules in H₂O, resulting in the larger radius of gyration and lager activation energies.