VDC－ACR共聚物熔点的变化规律与其结晶结构的关系

通过对偏氯乙烯（ＶＤＣ）和丙烯酸酯类（ＡＣＲ）单体共聚物熔点变化的测定，比较其与Ｆｌｏ－ｒｙ方程的偏离性，结合Ｍｏｎｔｅ－Ｃａｒｌｏ模拟及１ＨＮＭＲ的结果，推断了不同共聚单体对共聚物结晶性的影响以及共聚物的基本晶体结构。     

苯乙烯交联共聚中致孔剂的致孔作用.I

提出致孔剂在交联共聚中的作用是使其共聚物珠体内部发生分离，从而形成微孔。并分别从理论上阐明良溶剂，非良溶剂致孔作用，在良溶剂存在下，ＤＶＢ含量对共聚体的孔结构影响很大；在非良溶剂存在下，此得共聚体的孔径较大，其比表面积较小。     

苯乙烯交联共聚中致孔剂的致孔作用．Ⅰ

提出致孔剂在交联共聚中的作用是使其共聚物珠体内部发生相分离，从而形成微孔．并分别从理论上阐明良溶剂、非良溶剂的致孔作用．在良溶剂存在下，ＤＶＢ含量对共聚体的孔结构影响很大；在非良溶剂存在下，此得共聚体的孔径较大，其比表面积较小。     

醋酸乙烯酯－二乙烯苯大孔共聚物的合成及其结构性能的研究

制备了以醋酸乙烯酯（ＶＡｃ）为单体，以二乙烯苯（ＤＶＢ）为交联剂的共聚物小球．分别测定了它们的交联度，致孔剂的性质和用量，共聚时间等诸因素对共聚物的比表面积，孔容，平均孔径，表观密度和骨架密度的影响．     

新型五甲基茂基三苄氧基钛/甲基铝氧烷催化剂合成苯乙烯-乙烯共聚物及其表征

以五甲基茂基三苄氧基钛［Ｃｐ＊ Ｔｉ（ＯＢｚ）３］ 和甲基铝氧烷（ ＭＡＯ） 组成的催化体用本体法合成出苯乙烯 乙烯共聚物Ｐｏｌｙ（Ｓ ｃｏ Ｅ） ．考察了共聚温度,共聚时间,Ａｌ／Ｔｉ 摩尔比,主催化剂浓度［Ｔｉ］ 等条件对共聚反应的影响．共聚产物经沸丁酮,沸四氢呋喃（ＴＨＦ） 连续抽提分离,发现共聚物主要存在于ＴＨＦ 可溶级分中．可溶级分经ＤＳＣ,１３Ｃ ＮＭＲ,ＷＡＸＤ,ＤＭＡ 等手段分析,证明苯乙烯 乙烯共聚物为具有单一玻璃化转变温度（ Ｔｇ） 无熔融温度的无规共聚物,显示弹性体的粘弹性行为．     

基于Maple软件辅助绘制自由基二元共聚曲线的研究

运用数据处理软件(maple)对经典的自由基二元聚合公式进行图形绘制,得到了二元单体之间共聚关系的三组图。一是二元单体的自由基共聚曲线图F1-f1,二是聚合物中单体平均组成(Fp)与投料单体浓度(f1)的关系曲线图,三是聚合物转化率(C)与投料单体(f1)的关系曲线图。通过二组具有代表性的共聚实例,分别是有恒比点的非理想共聚(苯乙烯-丙烯腈共聚物)和非理想非恒比共聚(苯乙烯-乙酸乙烯酯共聚物)展现了绘图步骤和分析了不同竞聚率情况下的聚合物转化过程。     

在α-甲基苯乙烯二聚体调节作用下的苯乙烯-丙烯腈乳液共聚

<正> 由于苯乙烯(St)和丙烯腈(AN)竞聚率的差异,在乳液共聚中所得产物为组成不均匀的共聚物,因此一般在反应后期通过复杂计算和实验验证补加消耗快的单体,或采用回收大量单体等方法得到组成均匀的共聚物。St-AN乳液共聚物的分子量较大,产物不     

紫精的负离子对耐水的紫精—聚合物膜的光致变色性能的影响

将含不同负离子的苄基紫精分散在混合有ＰＶＰ的ＭＭＡ－ＨＥＭＡ共聚物基质中可制成耐水的光致变色膜。它们的光致变色速度的大小随紫精负离子的不同而有如下序列：Ｖ６（ＰＦ６＾－）〉Ｖ５（ＢＦ４＾－）￣Ｖ４（ＣｌＯ４＾－）〉Ｖ３（ＣＨ３－苯环－ＳＯ３＾－）〉Ｖ２（Ｂｒ＾－）￣Ｖ１（Ｃｌ＾－）。这与这些紫精在ＤＭＦ中的溶解度以及在共聚物基质中的溶解性大小的序列相一致。负离子对这些光致变色膜在空气中的氧化退色速     

六苯基取代联苯双酚/氢醌型共聚醚酮的研究

以 4 ,4′ 二氟二苯酮和不同比例的六苯基取代联苯双酚 /氢醌为单体 ,在温和条件下经溶液共缩聚合成了新型共聚醚酮 .采用13 C NMR技术测定共聚物中三种不同连接方式 (AKA ,DKD ,AKD)的平均链段长度(LA,LD) ,共聚物为短嵌段结构 .性能测试结果表明 ,新型共聚醚酮具有良好的溶解性、拉伸强度、较高的耐热性和良好的二氧化碳 /氮气和氧气 /氮气分离能力 .     

丙烯酸甲酯-异丁烯交替共聚反应机理和动力学研究

本文研究了丙烯酸甲酯(MA)和异丁烯(IB)在AlEtCl_2,BPO存在下的聚合反应机理及动力学。结果表明:当[IB]≥[MA]时,共聚合是按三元络合单体(T)均聚的机理进行,形成(MA)-(IB)的交替共聚物;当[IB]<[MA]时,则形成富MA的含MA嵌段序列的共聚物,共聚是由三元络合单体(T)和二元络合单体(B),按无规共聚机理进行的。     

Molecular dynamics simulations of trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadecalin-based polymer-bonded explosives

Molecular dynamics has been applied to investigate the low-sensitivity explosive TNAD (trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadecalin)-based polymer-bonded explosives (PBXs) with four typical fluorine polymers, PVDF (polyvinylidenedifluoride), PCTFE (polychlorotrifluoroethylene), F(2311) (fluorine rubber), and F(2314) (fluorine resin). The elastic constants, mechanical properties (tensile modulus, bulk modulus, shear modulus, and Poission ratio), binding energies, and detonation performances are first reported for the TNAD-based PBXs. The results show that the mechanical properties of TNAD can be effectively improved by the addition of small amounts of fluorine polymers, and the overall effect of fluorine polymers on the mechanical properties of the PBXs along three crystalline surfaces is (001) > (010) > (100). On each crystal surface, improvement in the ductibility made by the fluorine polymers changes approximately in the sequence of PVDF > F(2311) > F(2314) > PCTFE. The binding energies between different TNAD crystalline surfaces and different polymer binders with the same chain segment or mass fraction both decrease in the order of (010) > (100) > (001). The binding properties of the polymers with the same chain segment on each crystal surface of TNAD increase as PVDF < F(2311) < F(2314) < PCTFE, while those of different polymers in the same content decrease in the sequence of PVDF > F(2311) > F(2314) > PCTFE. The detonation performances of the PBXs decrease in comparison with the pure crystal, but they are superior to those of TNT.     

偏氟乙烯-三氟氯乙烯共聚物链结构的研究

用裂解气相色谱-质谱法(Py-GC/MS)研究了单体克分子比近于1:1的偏氟乙烯-三氟氯乙烯共聚物(F23)链结构。采用了居里点裂解器和裂解探针。质谱的鉴定结果表明,两种裂解器在一定条件下得到的F23裂解产物非常相似。根据这些裂解产物的化学结构,可以推断F23中两种单体的键接方式,并确定F23中占优势的链段排列为:(?)     

高分子化的阿司匹灵在水解过程中的荧光研究

<正> 近年来小分子化合物的高分子化引起人们广泛的注意。经高分子固定化(Immobilization)的小分子表现出一些原来并不具备的行为。利用荧光光谱来研究小分子经高分子化后发生的变化具有独特之处,我们曾用此法对小分子吖啶橙的高分子化问题进行过详细的研究。     

TATB基PBX结合能的分子动力学模拟

用分子动力学（MD）方法, 模拟计算了四种氟聚合物(聚偏二氟乙烯（PVDF）、聚三氟氯乙烯（PCTFE）、氟橡胶（F₂₃₁₁)、氟树脂(F₂₃₁₄))与TATB(1,3,5- 三氨基- 2,4,6- 三硝基苯)晶体的相互作用. 结果发现, 四种氟聚物与TATB的结合能大小排序为PVDF>F₂₃₁₁>F₂₃₁₄>PCTFE, 各氟聚物在TATB不同晶面上的结合能大小排序为(001)>(010)>(100), 结合能主要由分子间氢键决定.     

麦芽酸性磷酸酶的化学修饰及紫外光谱

本文研究化学修饰剂2,3-丁二酮(Butanedione)、β-巯基乙醇(Mercaptoethanol)、对硝基苯磺酰氟(4-Nitrobenzensulfonyl fluoride,NBSF)和焦碳酸二乙酯(Diethyl pyrocarhonate,DEPC)在不同浓度、不同时间条件下对麦芽酸性磷酸酶(ACPase,E.C.3.1.3.2)相互作用后的活力及紫外光谱的变化。结果表明:色氨酸和精氨酸可能是维系麦芽酸性磷酸酶催化功能的必需基团,酶分子中二硫键和组氨酸残基不参与该酶分子活性中心的构成。     

嵌段共聚物傅里叶变换拉曼光谱

用傅里叶变换拉曼光谱(FT-Paman)研究了聚环氧乙烷-聚环氧丙烷-聚环氧乙烷(PEO-PPO-PEO)嵌段共聚物的无水样品,发现某些谱带对PEO0-PPO-PEO嵌段共聚物的结构和构象变化敏感,其中某些峰的相对强度的PPO/PEO比率和共聚物的构象有关,研究表明PluronicF68和F88具有一些反式构象的螺旋结构,PluronicP103(P123)是无规则结构,其它的嵌段共聚物处于二者之间.     

Structure study of the furan–maleic anhydride copolymer

A structural study of furan–maleic anhydride copolymer (F–MAH) was undertaken to confirm its alternating nature and to determine its microstructure. The spectral properties of a model compound representing the alternating repeat unit, 2-(2-tetrahydrofuranyl)succinic anhydride, were compared with those of F–MAH. Their infrared (IR), ¹H, and ¹³C nuclear magnetic resonance (NMR) spectra (after compensating for the absence of the olefinic double bond) were in good agreement with those of the copolymer. Furthermore, the observed splitting in the ¹H- and ¹³C-NMR spectra of F–MAH were assigned to cis–trans linkages on both the F and MAH units, with cis linkage being favored on both units, especially the former. The structure of 2,5-dimethylfuran (DMeF)–MAH copolymer is similar to that of F–MAH copolymer, except that the preference of cis linkages is less pronounced. The structure of 2-methylfuran (MF)–MAH copolymer is a complex structure with numerous 2,3-furandiyl units. A mechanistic study was undertaken to elucidate the roles of F–MAH Diels–Alder adduct, and the charge-transfer (CT) complex in the radical initiated copolymerization. The adduct reverted substantially to monomers under the reaction conditions; but, the amount of adduct remaining at equilibrium was quite appreciable; therefore, its participation could be ruled out on this basis alone. However, on polymerizing the adduct in the presence of F-d₄, the latter was incorporated into the copolymer to an extent indicative of free monomer exchange. Therefore, the adduct cannot be directly involved in the polymerization.     

Dynamics of a single copolymer chain

The dynamics of a single copolymer chain in a solution containing identical chains is studied. The intermediate scattering function is calculated, and two different modes are identified and analyzed as a function of wave vector q. The first mode is characteristic of the copolymer system and leads to a peculiar constant relaxation frequency as q goes to zero. The second mode represents the diffusion of the chain in the solution.     

Study of Intermacromolecular Complex Formation Between Acrylamide—Vinyl Alcohol Graft Copolymer and Poly[Methacrylic Acid]

Acrylamide‐vinyl alcohol (AAm/VA) graft copolymer was prepared and characterized. The interaction of the graft copolymer with poly‐(methacrylic acid) (PMAA) in water was studied by several experimental techniques, such as viscometry, potentiometry, conductometry, IR spectra, and transmittance measurements. PMAA was found to interact with the graft copolymer in two distinct steps. The relative complexation ability of PAAm and PVA with respect to PMAA does not change when these polymers are present as parts of a graft copolymer chain.