丙烯酰胺与N,N′-亚甲基双丙烯酰胺的共聚反应研究

本文利用凝胶模量测定法、气相色谱法和紫外光谱法对丙烯酰胺与N,N’-亚甲基双丙烯酰胺水溶液共聚反应进行了研究,证实了N,N’-亚甲基双丙烯酰胺的反应活性明显大于丙烯酰胺的反应活性。用气相色谱法测得单体的竞聚率分别为r_(AM)=0.117,,r_(Bis)=5.756;用紫外光谱法研究了聚合反应中氧化还原引发剂浓度和反应温度对聚合反应速率的影响,得出共聚反应速率方程中,氧化剂的方次为0.66,还原剂浓度的方次为0.55,并求出共聚反应表现活化能为37.1KJ/mol。     

聚（N，N＇-二乙基丙烯酰胺）水凝胶的制备及其溶胀动力学

以N,N’-二乙基丙烯酰胺（DEA）为单体,偶氮二异丁腈（AIBN）为引发剂,分别采用疏水性的1,2-二乙烯苯（DVB）和水溶性的N,N’-亚甲基双丙烯酰胺（BIS）为交联剂制备了温度敏感水凝胶聚（N,N’-二乙基丙烯酰胺）（PDEA）。制得的PDEA水凝胶的低临界溶解温度（LCST）在30℃附近,初步讨论了交联剂的用量和性质对水凝胶性能的影响。并对其在不同温度下达到溶胀平衡时的溶胀比,去溶胀动力学及干凝胶的再溶胀动力学过程进行了研究。     

丙烯酰胺-N-羟甲基丙烯酰胺反相乳液共聚合

：以Ｓｐａｎ ４０ 为乳化剂,过硫酸铵为引发剂,进行了丙烯酰胺 Ｎ 羟甲基丙烯酰胺反相乳液共聚反应,研究了反应温度、单体浓度、引发剂浓度、乳化剂浓度等因素对聚合动力学的影响,并讨论了其聚合机理。     

新型含吡啶酰胺基希夫碱多齿配体的合成,光谱,晶体结构及抑菌活性研究

采用稀释法与胺5倍过量合成了一种新型的含吡啶环的开链二胺1a（N，N′-双(2-氨基乙基)－2，6-吡啶二甲酰胺）。此外，合成了六个新型多齿希夫碱配体N，N′－双(β－R－苯甲醛亚胺基乙基)－2，6－吡啶二甲酰胺[其中，R=H(2a)，o-OH(2b)，p-OH(2c)，m-NO₂(2d)，p- N(CH₃)₂(2e)]及N，N′-双[γ-水杨醛亚胺基正丙基]－2，6－吡啶二甲酰胺2f。通过元素分析,紫外－可见光谱，红外光谱，氢核磁共振谱及质谱对化合物进行了表征。通过化合物2e的单晶结构X－射线单晶衍射分析表明该晶体属于立方晶系P－1空间群，其晶胞参数为：a=11.010(2) nm，b=13.865(3) nm，c=9.6537(19) nm，α=102.77(2)º，β=92.07(3)º，γ=87.98(3)º，V=1435.7(5) nm³，Z=2，D_c=1.230 mg•cm^-3，M_r=531.66。微量热法检测了化合物对大肠杆菌的抑制作用，并初步分析了化合物结构与抗菌活性之间的关系。实验结果表明，所有化合物都对大肠杆菌有抑制作用，其中水杨醛希夫碱的抑菌活性最好。     

超声波合成温敏型聚合物——聚(N-异丙基丙烯酰胺)

以N-异丙基丙烯酰胺为单体,N,N′-亚甲基双丙烯酰胺为交联剂,THF为溶剂,采用超声辐照聚合法合成了一种温敏型聚合物——聚(N-异丙基丙烯酰胺)(1),其结构经FT-IR表征.用UV-Vis研究了1的热相转变性能.结果表明,1具有温度敏感性,其最低临界共溶温度为34℃.     

N-异丙基丙烯酰胺温度敏感性水凝胶相转变动力学研究及其应用

 研究指出表观二级动力学方程可以很好地描述N-异丙基丙烯酰胺水凝胶的溶胀和消溶胀动力学.即溶胀动力学方程为dR/dt=k₁(R_e-R)²,消溶胀动力学方程为-dR/dt=k_c(R-R_e)².把这种水凝胶用于分离高分子水溶液时可引入“单位溶张比分离循环的合理时耗”这样一个参量.它根据溶胀和消溶胀过程中的起始溶胀比、平衡溶胀比、表观溶胀动力学常数和表观消溶胀动力学常数求出.具体公式为△t₁(T_s,T_c)=2/[R_c(T_s)-R₀(T_s)]²k_s(T_s)+15/[R₀(T_c)- R_s(T_c)]²k_c(T_c)^1/2在理想情况下,分离过程的“总合理时耗”与△t_1成正比,比例系数为分离过程中的除水总量与干凝胶用量的比值,即△t_r=W_W/WG·△t₁.当根据二个动力学方程求得的总时耗计算值处于(0.9△t_r,1.1△t_r)范围内时,表明所选干凝胶用量和循环溶胀比区段均合适.     

丙烯酸甲酯与N-对卤苯基甲基丙烯酰胺共聚合的研究

<正> 我们已经报道过甲基丙烯酸甲酯与N-对卤苯基甲基丙烯酰胺共聚合的研究。本文工作合成了丙烯酸甲酯与N-对卤苯基甲基丙烯酰胺共聚体,研究了这二组共聚体系的聚合反应、共聚体的组成、估算了单体的竞聚率,比较了这两种酰胺对丙烯酸甲酯与甲基丙烯酸甲酯的反应活性。     

丙烯酸与丙烯酰胺共聚制备高吸水性树脂

采用溶液聚合法,以N,N’-亚甲基双丙烯酰胺（NMBA）为交联剂,过硫酸钾（KPS）为引发剂合成了高吸水性树脂聚（丙烯酸-丙烯酰胺）（P（AA—AM））,研究了单体配比、丙烯酸中和度、引发剂及交联剂用量、反应温度对树脂在去离子水和0．9％盐水中吸水率的影响．最佳条件下制备的树脂在去离子水中吸水率为750g·g^-1,在0．9％盐水中吸水率为85g·g^-1．     

4,4′-偶氮二[4-氰基戊酰(对-二甲基氨基)苯胺]引发丙烯酰胺聚合及其动力学研究

以N,N-二甲基甲酰胺(DMF)为溶剂,研究了4,4′-偶氮二[4-氰基戊酰(对-二甲基氨基)苯胺](ACPDA)为引发剂引发丙烯酰胺(AAM)的聚合行为.考察了聚合反应温度、单体浓度和引发剂浓度对聚合物分子量和聚合反应速率的影响,测定了反应级数和聚合反应的活化能.实验结果表明,ACPDA引发AAM的聚合速率方程为Rp=K[AAM]1.03[ACPDA ]0.48,聚合反应的表观活化能(Ea)为126.44kJ·mol-1.     

N-异丙基甲基丙烯酰胺共聚热缩温敏水凝胶

从甲基丙烯腈与异丙醇反应制备了N-异丙基甲基丙烯酰胺(NIPM),研究了其以N,N′-亚甲基双丙烯酰胺(MBA)为交联剂在不同溶剂体系的聚合及所形成的水凝胶的性质。表明NIPM-MBA凝胶具有热缩温敏性。在NIPM-MBA体系引入丙烯酸钠、甲基丙烯酸钠等负离子单体时,凝胶的溶胀比明显增加,MBA所占比例较少的体系,具有热缩、热胀双重性。     

Water-soluble copolymers. XII. Copolymers of acrylamide with sodium-3-acrylamido-3-methylbutanoate: Synthesis and characterization

The copolymerization of acrylamide (AM) with sodium-3-acrylamido-3-methylbutanoate (NaAMB) has been studied. The value of r₁r₂ has been determined to be 0.56 for the AM–NaAMB pair. The molecular weights of the copolymers were relatively unaffected by monomer feed ratios. The copolymer microstructures, including run numbers and sequence distributions, were calculated from the reactivity ratios. The solution properties of the AM–NaAMB copolymers, as well as the NaAMB homopolymer, will be reported in a subsequent paper.     

Water-Soluble Copolymers. XIX. Copolymers of Acrylamide with Sodium 3-(N-Propyl)acrylamido-3-Methylbutanoate: Synthesis and Characterization

The copolymerization of acrylamide (AM) with sodium 3-(N-propyl)acrylamido-3-methlbutanoate (NaPAMB) has been studied in the range from 40 to 90% AM in the feed. The copolymer compositions have been determined from elemental analysis and ¹³C NMR. Reactivity ratio studies have been performed, and the value of r₁r₂ determined to be 0.36. The molecular weights, as determined by low-angle laser light scattering of the copolymers, were found to decrease sharply with increasing NaPAMB content, and were in the range 0.5–7.0 × 10⁶. The copolymer microstructures, including mean sequence length distributions, were calculated from the reactivity ratios. Knowledge of polymer composition, micro-structure, and molecular weight is utilized for assessment of structure/dilute solution property relationships reported in a subsequent paper in this series.     

Copolymerization of ethylene and 1-butene with highly active Ticl4/THF/Mgcl2, Ticl4/THF/Mgcl2/SiO2, and TiCl3.1/3AlCl3 catalysts

Highly active catalysts for copolymerization have been prepared by the precipitation of MgCl₂/ToCl₄ complex with or without high surface area silica. Copolymerization of ethylene and 1-butene has been tested by using the prepared catalysts at various concentrations of 1-butene. The catalytic activities are 20–80 kg/g Ti h. The rate of copolymerization is strongly affected by the addition of 1-butene. The decay rate of copolymerization is first order with respect to time. Analyses of copolymers with solvent extraction, DSC, IR, XRD, and NMR were performed. Ethylene reactivity ratio (k₁₁) for TiCl₄/MgCl₂/THF catalyst is calculated to be about 26 by NMR spectrum. © 1994 John Wiley & Sons, Inc.     

二乙基二烯丙基氯化铵均聚及其与丙烯酰胺或丙烯酸共聚动力学研究

采用膨胀计法研究了以过硫酸铵为引发剂,二乙基二烯丙基氯化铵(DEDAAC)在水溶液中的均聚及其与丙烯酰胺(AM)和丙烯酸(AA)共聚动力学,测定了相应的聚合表观活化能;采用元素分析法测定了DEDAAC分别与AM和AA在低转化率下共聚物的组成,并采用氯离子选择性电极法测定了DEDAAC-AM共聚物中的氯离子含量,按Kelen-Tudos方法求得了相应的竞聚率.结果表明,DEDAAC均聚速率方程为RP=k[M]0.99[I]0.76,表观活化能Ea=77.00kJ/mol,说明链终止为单基终止和双基终止并存,引发过程与单体浓度无关;DEDAAC与AM在摩尔比为4∶1时,共聚动力学方程为RP=[M]2.53[I]0.90,表观活化能Ea=67.06kJ/mol,单体竞聚率为rDE=0.31±0.02、rAM=5.27±0.53;DEDAAC与AA在摩尔比为4∶1时,共聚动力学方程为RP=k[M]2.94[I]0.83,表观活化能Ea=70.07kJ/mol,竞聚率为rDE=0.28±0.03、rAA=5.15±0.28;DEDAAC与AM和AA等共聚为非理想共聚,得到的产物均为无规共聚物.     

Cationic surfmers with benzyl groups: Synthesis and copolymerization with acrylamide

A series of cationic surfmers with benzyl groups（QARBCs）with different R groups on the benzene ring were synthesized and characterized by IR,¹H-NMR,¹³C-NMR.The aggregation of QARBCs was studied by the steady-state fluorescence technique.It turned out that QARBCs had surface activity and their critical micelle concentration（CMC）values varied in the range of 10^-2—10^-3mol/L with slight increase with temperature.The copolymerization of acrylamide（M₁）and QARBCs（M₂）was studied below and above CMC,their reactivity ratios were determined by the Finemann-Ross method.It was found that below CMC,copolymerization took place in a homogeneous system and reactivity ratios of acrylamide and QARBCs were less than 1;while above CMC,reactivity ratios of QARBCs were greater than 1.The copolymerization mechanism of QARBC was observed to be similar to that of micellar polymerization.QARBCs tended to homopolymerization,which gave rise to micro-blocky sequences in the polymer backbone.The Q and e values of QARBCs were calculated according to the Alfrey-Price equation by using r_1（AM）and r_2（qarBC）.Samples of poly（AM-co-QARBC） were prepared above and below CMC and their hydrophobic associations were studied by the steady-state fluorescence spectra and 2D NOESY spectra,and their critical associating concentrations（CAC）were estimated.The results showed that samples of poly（AM-co-QARBC）prepared above CMC had stronger hydrophobic association in aqueous solution than those prepared below CMC.     

Radiation-induced copolymerization of methyl trifluoroacrylate with propylene

Copolymerization of methyl trifluoroacrylate (MTFA) with propylene in bulk was induced by γ irradiation. A wide range of the initial monomer composition gives an equimolar alternating co-polymer. The reactivity ratios of r₁ (MTFA) and r₂ (propylene) were determined to be 0.01 and 0.005, respectively. The polymerization rate at an equimolar monomer composition is proportional to the 1.0 power of the dose rate. The dose rate dependency of higher than 0.5 may be ascribed to unimolecular termination due to a degradative chain transfer of propagating radicals to propylene. The G values of the initiating radical formation and the polymerization reaction were calculated to be 1.78 and 1336, respectively. The dependence of the copolymerization rate on the temperature was small, and the activation energy of copolymerization was 1.1 kcal/mole from ?6 to 50°C.     

Copolymerization of trifluoropropene with itaconic acid and ethylvinylether by using gamma rays

Copolymerization of trifluoropropene (TFP) with itaconic acid (IA) and ethylvinylether (EVE) have been carried out by using gamma rays from a ⁶⁰Co source. Copolymers of TFP-IA and TFP-EVE were white powder and white grease, respectively. The copolymerization rate of TFP-IA system is proportional to 0.64 power of dose rate and that of TFP-EVE system is proportional to 1.0 power of dose rate. The apparent activation energy for TFP-IA system is 4.3 kcal/mol and it is 10 kcal/mol for TFP-EVE system. The copolymerizations of both TFP-IA and TFP-EVE are inhibited remarkably by a radical scavenger, PBQ. The reactivity ratios for those systems were determined roughly to be r_TFP = 0.55, r_IA = 13 and r_TFP = 0.30, r_EVE = 0.20.     

Effect of Substituents on the Copolymerization Parameters of Some Phenolic Monomers

Copolymerization parameters of some halogen substituted phenolic monomers have been determined by the linear graphical method of Kelen and Tüdös. The order of reactivity of p-chlorophenol, p-bromophenol and p-iodophenol is found to be the reverse of the order of electronegativity of their halogen substituents when they are copolymerized with p-hydroxy-benzoic acid. On copolymerization with p-cresol, these halogen substituted phenols have reactivity in the same order as the electronegativity of their substituents. This reversal of reactivity of phenolic monomers has been interpreted in terms of (1) opposite polarization caused by electrophilic or nucleophilic substituents present in the common monomers, and (2) the magnitude of their resonance stabilization.

The copolymerization parameters r₁ and r₂ are universally used for the characterization of monomer pairs with regard to their behavior in copolymerization. The classic copolymer equation describes the composition of the copolymer as a function of the reactivity ratios and the composition of the monomer feed. Several authors have used linear [1], nonlinear [2–6], specific coper composition equations [7], and computer programming routines [8] for calculating copolymerization parameters r_l and r₂. Kelen and Tödös [9] have recently.     

Free Radical Copolymerization of N‐Cyclohexylmaleimide with Cyclohexene

The radical copolymerization of cyclohexene (M₁) and N‐cyclohexylmaleimide (M₂) was carried out with 2,2′‐azobis(isobutyronitrile) as an initiator in various solvents at 55°C. The copolymerization of cyclohexene with N‐cyclohexylmaleimide in chloroform, dioxane and benzene proceeded in a homogeneous system to give an alternating copolymer when the monomer of cyclohexene was over 40 mol% in the feed. It was found that the initial rate of the copolymerization (R_p), as well as the number‐average molecular weight of copolymers, were dependent on the monomer composition and was at maximum at about 30 mol% of cyclohexene in the feed. The effects of solvents on the R_p and reactivity ratios were also investigated in this copolymerization system. The copolymerization in dioxane produced a higher R_p than that in chloroform and benzene, and the monomer reactivity ratios were found to be r₁=0, r₂=0.032 in chloroform; r₁=0, r₂=0.065 in benzene and r₁=0, r₂=0.14 in dioxane, respectively.