【作者】 杨雪娇；

【导师】 方岩雄； 张焜；

【作者基本信息】 广东工业大学 ， 应用化学， 2015， 博士

【摘要】 本文研究了几种阴离子或者阳离子带不饱和化学键的可聚合离子液体的合成与表征,并研究了可聚合离子液体交联共聚物凝胶的合成及其吸液保液性能与机理,探索了可聚合离子液体交联共聚物凝胶在难水溶香精缓释领域的应用。研究了阳离子带不饱和化学键的可聚合离子液体的合成、表征及其交联共聚物凝胶的合成与吸液性能。以丙酮为溶剂,甲基丙烯酸-N,N’-二甲胺基乙酯(DMAEMA)与等摩尔丙酸(AS)中和后过滤,减压脱除溶剂,得到无色透明的DMAEMA-AS可聚合离子液体。采用同样方法,用磷酸中和DMAEMA,所得沉淀经真空干燥后可得到白色DMAEMA-H3PO4可聚合离子液体。两种可聚合离子液体的相变温度分别为-61.9℃、76.2℃。以过硫酸铵(APS)为引发剂,以N.N’-亚甲基双丙烯酰胺(MBAM)为交联剂,甲基丙烯酸-2-羟基乙酯(HEMA)分别与两种可聚合离子液体在水溶液中交联共聚,得到Poly(HEMA-co-DMAEMA-AS/H3P04)交联共聚物凝胶,对水和多种有机溶剂具有吸收作用。EMA在聚合反应单体中的质量分数不超过55%,其用量对两种凝胶的吸液性能没有明显影响；HEMA的用量进一步增大,则导致凝胶的吸液性能急剧下降。研究了阴离子带不饱和化学键的可聚合离子液体的合成、表征及其交联共聚物凝胶的合成与吸液性能。在室温搅拌条件下将AMPS分散到丙酮中,逐滴滴加丁胺(BA)液体中和,过滤后旋转蒸发去除丙酮,得到淡黄色透明的粘稠AMPS-BA可聚合离子液体,其相变温度为-47.7℃。以APS为引发剂,以MBAM为交联剂,DMAEMA为共聚单体,采用水溶液聚合法可合成Poly(AMPS-BA-co-HEMA)交联共聚物凝胶,对水以及多种有机溶剂具有吸收作用,吸收丁胺可达18.8g/g,吸水可达120.3 g/g。如果HEMA在反应单体混合物中的质量比低于15wt%,共聚产物没有吸液性能；HEMA在反应单体混合物中的比例超过90wt%的时候,共聚产物不再吸收甲醇和苯甲醇,但可以吸收少量水和二甲基亚砜。研究了共聚单体的性质对可聚合离子液体交联共聚物凝胶吸液性能的影响。分别以水以及苯为溶剂,采用溶液聚合法合成了DMAEMA-AS以及AMPS-BA可聚合离子液体与丙烯酰胺、丙烯酸钠以及苯乙烯的交联共聚物凝胶,发现Poly(DMAEMA-AS-co-AANa)以及Poly(AMPS-BA-co-AANa)均只吸水而不吸收有机溶剂；Poly(DMAEMA-AS-co-AAm)以及Poly(AMPS-BA-co-AAm)均只能吸收水和二甲基亚砜,不吸收其它有机溶剂；苯乙烯与DMAEMA-AS以及AMPS-BA可聚合离子液体的交联共聚物均不吸水,但能够吸收多种有机溶剂,Poly(DMAEMA-AS-co-St)可以吸收己烷、环己烷、苯、甲苯、二氯甲烷、氯仿、甲醇、乙醇,而Poly(AMPS-BA-co-St)可吸收己烷、环己烷、苯、甲苯、二氯甲烷、氯仿、甲醇、乙醇以及甲基丙烯酸甲酯。研究了可聚合离子液体的交联共聚物凝胶的保液性能。分别采用静态加压法、加热法以及高速离心法,测定了可聚合离子液体的交联共聚物吸收水、DMSO以及苯形成的凝胶的保液性能,发现凝胶具有良好的加压保液性能,在分别施加100g或者500g静态压力的情况下,其保液率没有明显区别,均超过98%。与医用脱脂棉相比,可聚合离子液体的交联共聚物凝胶具有良好的加热保液性能,可以显著地抑制吸收液体的挥发。可聚合离子液体的交联共聚物吸收液体之后的凝胶具有良好的离心保液性能,在高速转动条件下吸收的液体几乎没有损失,而医用脱脂棉的离心保液性能较差。研究了可聚合离子液体的交联共聚物凝胶的吸液保液机理。液体溶剂分子与可聚合离子液体交联共聚物的高分子链以及自由离子的极性相近或者内聚能密度相近、或者能够发生溶剂化作用,使溶剂分子能够自发地与高分子链以及自由离子混合；与此同时,交联共聚物中的离子液体基团处于电离状态,因电离而产生的自由离子在溶剂中的热运动使之远离高分子离子,使高分子离子上点电荷之间的静电排斥作用超越高分子离子与自由离子之间的静电吸引作用,交联高分子链充分舒展,交联网络充分张开而能够容纳大量液体溶剂分子,产生超强吸液现象。探索了可聚合离子液体交联共聚物凝胶在香精缓释领域的应用。利用Poly(DMAEMA-AS-co-HEMA)凝胶既能够吸水成为水凝胶、又能够吸收乙醇成为乙醇凝胶、香兰素易溶于乙醇而难溶于水的原理,将香兰素溶解于95%乙醇后被Poly(DMAEMA-AS-co-HEMA)干凝胶吸收后脱除乙醇、再吸水成为水凝胶,将香兰素负载于Poly(DMAEMA-AS-co-HEMA)凝胶中,其负载能力远远超过吸收香兰素的饱和水溶液。Poly(DMAEMA-AS-co-AAm)干凝胶吸收香兰素乙醇溶液的性能随溶液浓度增大而稳步下降,但负载香兰素的性能先稳步提高、随后略有提高而增加幅度很小。香兰素负载量较低的Poly(DMAEMA-AS-co-AAm)干凝胶在碳酸钠-碳酸氢钠缓冲溶液中的溶胀速度很快,60min基本达到平衡溶胀。香兰素从Poly(DMAEMA-AS-co-AAm)凝胶中释放的速度较快,24h内释放率可达60%以上,并且香兰素在Poly(DMAEMA-AS-co-AAm)凝胶中的负载量越低其释放率越高。更多还原

【Abstract】 In this work, a series of polymerizable ionic liquids with unsaturated chemical bond(s) on the cations and/or the anions were synthesized and characterized, their crosslinked copolymeric gels with other monomers were syntheized, the properties of swelling in water and a seires of organic solvents and retaining the absorbed liquids of the gels were inestigated, the mechanism to swell in solvents as well as to retain liquids were investigated as well.Synthesis and characterization of the polymerizable ionic liquids with unsaturated chemical bond(s) on the cations were investigated, the swelling properties of their copolymeric gels with 2-hydroethyl methylacrylate (HEMA) were investigated as well. By using acetone as the solvent, N,N’-dimethylaminoethyl methylacrylate (DMAEMA) was nertralized with propionic acid (AS) or phosphoric acid, to give DMAEMA-AS or DMAEMA-H3PO4 polymeric ionic liquid, respectively. The glass transition temperatures (Tg) of the two polymerizable ionic liquids were -61.9℃ and 76.2 ℃, respectively. By using ammonium persulfate (APS) as an initiator, N,N’-methylene-bis-acrylamide (MBAM) as a crosslinker, the crosslinked copolymeric gels of DMAEMA-AS or DMAEMA-H3PO4 with HEMA were synthesized. The resulted poly(HEMA-co-DMAEMA-AS/H3P04) gels can swell in both water and a series of organic solvents; the absorbency for benzyl alcohol was 52.1 g/g and 23.6g/g respectively, and the absorbency for water was 103.6 g/g and 89.3 g/g respectively. If the weight percentage of HEMA was less than 55%, the HEMA dosage didn’t influence the swelling property of the gels; the swelling property decreased drastically when the HEMA dosage increased for more than 55wt%.Synthesis and characterization of the polymerizable ionic liquids with unsaturated chemical bond(s) on the anions were investigated, the swelling properties of their copolymeric gels with 2-hydroethyl methylacrylate (HEMA) were investigated as well. By using acetone as the solvent,2-acrylamido-2-methyl-propane sulfonic acid (AMPS) was neutralized with butylamine (BA), followed by filtration and the filtrate was evaporated, pale yellow and sticky AMPS-BA polymerizable ionic liquid was obtained, The glass transition temperatures (Tg) was -47.7 ℃. By using APS as an initiator, MBAM as a crosslinker, the crosslinked copolymeric gels of AMPS-BA with HEMA were synthesized. The resulted poly(HEMA-co-AMPS-BA) gels can swell in both water and a series of organic solvents; the absorbency for butylamine was 18.8 g/g, and the absorbency for water was 120.3 g/g. If the weight percentage of HEMA was less than 15%, the copolymeric gels didn’t swell in any solvent; the copolymeric gels can only swell in water and DMOS when the HEMA dosage was more than 90wt%.Influence of co-monomers on swelling property of the copolymeric gels of the polymerizable ionic liquids was investigated. By using water or benzene as solvent, copolymeric gels of DMAEMA-AS and AMPS-BA with acrylamide (AAm), sodium acrylate (AANa) or styrene (St) were synthesized, their swelling property in water and a series of organic solvents was investigated as well. It has been found that poly(DMAEMA-AS-co-AANa) gels and poly(AMPS-BA-co-AANa) gels can only swell in water, poly(DMAEMA-AS-co-AAm) gels and poly(AMPS-BA-co-AAm) gels can only swell in water and DMSO, while poly(DMAEMA-AS-co-St) gels and poly(AMPS-BA-co-St) gels cann’t swell in water. Both poly(DMAEMA-AS-co-St) and poly(AMPS-BA-co-St) gels can swell in hexane, cyclohexane, benzene, toluene, dichloromethane, chloroform, methanol and ethanol.The property of retaining absorbed solvents was investigated by applying static pressure on the gels, heating the gels, and centrifugatting the gels. The results showed that when 100g and 500g static pressure was applied on the hydrogels, DMSO gels or benzene gels of poly(DMAEMA-AS-co-AAm) or poly(AMPS-BA-co-St), more than 98% absorbed solvents were retained. In contrast, less than 20% absorbed solvents were retained when 100g static pressure was applied on cotton, and no abosrbed solvents was retained when 500g static pressure was applied on cotton. Compared with cotton, volatilization of the absorbed solvents was obviously controlled by the gels when the samples were heated or centrifugated.The mechanisms for swelling as well as retaining solvents of the copolymeric gels of polymerizable ionic liquids were investigated. Similar polority, similar cohensive energy density, or solvation possibility of the solvents and the macromolecular chains as well as the free mobile ions induces the solvents spontaneously mix with the crosslinked polymer; at the same time, dissociation of ion pairs on backbone of the crosslinked polymer induces electrostatic repulsion of macromolecular ions, which makes expansion of the crosslinked networks. Thus, many solvents can be absorbed.The application of co-polymeric gels of polymerizable ionic liquids in delayed release of hydrophobic edible essence was explored. As vanillin is soluble in ethanol which insoluble in water, vanillin was dissolved in 95% ethanol followed by the solution being absorbed by poly(DMAEMA-AS-co-HEMA) xerogel. The resulted gels was dried, followed by swelling in water to give vanillin-uploaded hydrogels. By this means, the uploading capacity of vanillin onto the gels was greatly improved. The absorbency of poly(DMAEMA-AS-co-HEMA) xerogel for 95% ethanol containing vanillin decreased when the vanillin concentration increased, while the uploading capacity of vanillin increased. When swell in Na2CO3-NaHCO3 buffer solution with pH value 8.0, the poly(DMAEMA-AS-co-HEMA) xerogel with lower vanillin-uploading reached equilibrium swelling in 60min, while The poly(DMAEMA-AS-co-HEMA) xerogel with higher vanillin-uploading reached equilibrium swelling in 100min. Vanillin released quickly from the gels in Na2CO3-NaHCO3 buffer solution with pH value 8.0; more than 60% vanillin released from the gels in 24 hours. The order of release kenetics was one.更多还原