【作者】 翁婷婷；

【导师】 郭建维；

【作者基本信息】 广东工业大学 ， 应用化学， 2013， 博士

【摘要】 本文以带不饱和键的可聚合有机强酸2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为原料,采用酸碱中和方法,合成了基于AMPS的可聚合离子液体；采用共聚方法,选择合适的共聚单体与基于AMPS的可聚合离子液体交联共聚,制备了一系列交联共聚物凝胶；并以氯霉素为模型药物,研究了凝胶的药物负载与药物缓释性能。研究了基于AMPS的可聚合离子液体的合成。将AMPS分散在丙酮中,搅拌滴加三乙胺(TEA)至白色粉末完全消失,再常温减压蒸馏去除溶剂,得到淡黄色粘稠状的AMPS-TEA可聚合离子液体,DSC表征结果表明该离子液体的熔点为-59.4℃。采用相同方法,以咪唑(iMz)中和AMPS,得到淡黄色粘稠状的AMPS-iMz可聚合离子液体,DSC表征结果表明该离子液体的玻璃化温度为34℃。研究了一系列AMPS-TEA以及AMPS-iMz可聚合离子液体的交联共聚物凝胶的合成与吸液保液性能。采用水溶液聚合法,以N,N’-亚甲基双丙烯酰胺为交联剂,以过硫酸铵为引发剂,AMPS-TEA可聚合离子液体与丙烯酰胺(AAm)交联共聚合成了Poly(AMPS-TEA-co-AAm)无色透明的玻璃状凝胶,吸收去离子水218g/g,吸收生理盐水50g/g。 Poly(AMPS-TEA-co-AAm)凝胶对多种有机溶剂具有超强吸收作用,对有机溶剂的吸收性能与该溶剂的极性没有明显关系。Poly(AMPS-TEA-co-AAm)凝胶吸收水或者有机溶剂之后,成为无色透明、具有一定弹性、并可以保持恒定形状的玻璃状凝胶。与普通吸液材料海棉相比,Poly(AMPS-TEA-co-AAm)凝胶具有良好的保液性能,在离心、施加静态压力的条件下,可以显著地抑制吸收的液体从凝胶中溢出；在加热条件下,可以显著地抑制吸收的液体的挥发。AAm对Poly(AMPS-TEA-co-AAm)凝胶的吸液性能具有重要的影响。AAm的添加比例低于15wt%, Poly(AMPS-TEA-co-AAm)凝胶是粘稠的膏状,没有吸收水或者有机溶剂的能力；AAm的添加比例超过95wt%, Poly(AMPS-TEA-co-AAm)凝胶仍然具有吸水性能,但不再吸收有机溶剂。采用水溶液聚合法,AMPS-iMz可聚合离子液体分别与AAm、丙烯酸(AANa)共聚合成了Poly(AMPS-iMz-co-AAm)、 poly(AMPS-iMz-co-AANa)凝胶。在实验范围内,Poly(AMPS-iMz-co-AAm)凝胶吸水186g/g、吸收二甲亚砜267g/g,不能吸收其它有机溶剂；而poly(AMPS-iMz-co-AANa)凝胶只能吸水(351g/g),不能吸收有机溶剂。以苯为溶剂,采用溶液聚合法,AMPS-iMz可聚合离子液体分别与甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BMA)共聚合成了poly(AMPS-iMz-co-MMA)、 poly(AMPS-iMz-co-BMA)凝胶。在实验范围内,两种凝胶不吸水,对苯、甲苯、环已烷、甲基丙烯酸甲酯、丁酮等有机溶剂具有吸收作用；两种凝胶对有机溶剂的吸收能力体现出如下规律性：(a)对有机溶剂的吸收能力与该溶剂的介电常数没有直接关系；(b)对于同分异构体,对正构体的吸收能力超过对异构体的吸收能力；(c)对于同系物,碳原子数越多,对该有机溶剂的吸收能力越低。研究了基于AMPS的可聚合离子液体的交联共聚物的超强吸液机理,提出在于高分子主链与溶剂具有相容性、离子液体基团处于完全状态、以及自由离子与溶剂具有相容性。基于AMPS的可聚合离子液体的交联共聚物的超强保液机理,在于排出吸收的液体,需要克服高分子主链上相同电荷基团之间的静电排斥力,需要消耗更多的能量。研究了Poly(AMPS-TEA-co-AAm)干凝胶对氯霉素负载行为,发现Poly(AMPS-TEA-co-AAm)干凝胶对氯霉素溶液的吸收量,与其对纯溶剂的吸收量相比没有明显变化,而无水乙醇中氯霉素浓度对Poly(AMPS-TEA-co-AAm)干凝胶吸收各种浓度溶液的性能没有明显影响,干凝胶吸收浓度为1.0wt%的氯霉素无水乙醇溶液与吸收不含氯霉素的无水乙醇相同,表明Poly(AMPS-TEA-co-AAm)凝胶的溶质(氯霉素)浓度敏感性不存在或者不明显。分别以水、甲醇、乙醇、乙二醇、异丙醇、1,3-丙二醇、丙三醇、正丁醇为溶剂,采用Poly(AMPS-TEA-co-AAm)干凝胶吸收氯霉素的溶液后再脱除溶剂的方法,将氯霉素负载于凝胶中,在溶液浓度相同的条件下,负载量主要取决于该干凝胶对溶剂的吸收能力；对于相同溶剂,氯霉素浓度与其负载量呈线性关系。X射线衍射结果表明,在氯霉素负载量较低的情况下,氯霉素完全以分子状态分散于Poly(AMPS-TEA-co-AAm)干凝胶的交联高分子网络中,没有晶体状态的氯霉素存在；在氯霉素负载量较高的情况下,多数氯霉素在交联高分子聚合物中以晶体状态存在,而晶体中的部分氯霉素分子与高分子之间发生氢键相互作用,导致其结晶状态改变。负载氯霉素的Poly(AMPS-TEA-co-AAm)干凝胶的药物释放过程包括凝胶溶胀而导致被高分子链缠绕的氯霉素与水分子发生接触、氯霉素溶解于凝胶内部的自由水中、氯霉素分子从凝胶内部溶液向凝胶外部溶液扩散等三个步骤。载药干凝胶在去离子水、生理盐水以及磷酸盐缓冲溶液PBS中的溶胀速度很快,一般在200min左右即可达到饱和溶胀。氯霉素负载量越大,载药干凝胶吸收水溶液达到饱和时的吸水量越低。在去离子水、生理盐水以及磷酸盐缓冲溶液(PBS)中,氯霉素从Poly(AMPS-TEA-co-AAm)凝胶中的释放速度很快,经过60-120min的释放,氯霉素的累计释放率不再增加,而此时各种氯霉素负载量的凝胶,其氯霉素累计释放率已经达到40-90%左右,并且干凝胶中氯霉素的负载量越大,其氯霉素累计释放率越低。更多还原

【Abstract】 Polymerizable room temperature ionic liquids (RTILs) were synthesized by neutralization of2-acrylamido-2-methyl-l-propane sulfonic acid (AMPS) and triethylamine (TEA) or imidazole (iMz). Co-polymeric gels based on such RTILs were synthesized by solution copolymerization; the swelling properties in water and organic liquids of the gels were investigated. By using chloramphenicol as a model drug, uploading and release of water insoluble drugs onto Poly(AMPS-TEA-co-AAm) gels were investigated.Synthesis of AMPS-based RTILs were investigated. By using acetone as a solvent, AMPS was neutralized with TEA and iMz followed by evaporation of the solvent, to give AMPS-TEA and AMPS-iMz RTIL, respectively. The two RTILs were characterized with FT-IR and1H-NMR. DSC data showed the glass transition temperature was-59.4℃for AMPS-TEA, and34℃for AMPS-iMz.A series of co-polymeric gels based on AMPS-TEA and AMPS-iMz were synthesized, their swelling properties in water and a series of organic liquids were investigated. Firstly, Co-polymeric gels of Poly(AMPS-TEA-co-AAm) were synthesized by co-polymerizing AMPS-TEA with acrylamide (AAm) in aqueous solutions using N,N’-methylenebisacrylamide (MBAm) as a crosslinker, and ammonium persulfate (APS) as an initiator. The results showed that Poly(AMPS-TEA-co-AAm) were transparent and glassy gels. Poly(AMPS-TEA-co-AAm) gels exhibited superabsorbency in both water and a series of organic liquids. There was no obvious relationship between absorbency and dielectric constant of the liquids being absorbed by the gels. Poly(AMPS-TEA-co-AAm) gels exhibited good liquids retaining property; the liquids being absorbed were kept without spillage under static pressure and centrifugation.The swelling property of Poly(AMPS-TEA-co-AAm) was seriously influenced by AAm content in the gels. Poly(AMPS-TEA-co-AAm) did not show any absorbency if the feeding ratio of AAm was less than15wt%; and Poly(AMPS-TEA-co-AAm) can swell in water while can not swell in any organic liquids if the feeding ratio of AAm was more than95wt%.Co-polymeric gels of AMPS-iMz and AAm or sodium acrylic acid (AANa) were synthesized by aqueous solution copolymerization; their swelling property were investigated. The results showed that the absorbency of Poly(AMPS-iMz-co-AAm) was186g/g and267g/g for water and DMSO respectively; and Poly(AMPS-iMz-co-AAm) can not swell in other organic liquids. Poly(AMPS-iMz-co-AANa) can only swell in water. Co-polymeric gels of AMPS-iMz and methylmethylate (MMA), butylmethylate (BMA) were synthesized respectively by solution copolymerization using benzene as a solvent, and divinylbenzene (DVB) as a crosslinker. Both poly(AMPS-iMz-co-MMA) and poly(AMPS-iMz-co-BMA) can not swell in water; while they can swell in benzene, toluene, cyclohexane, butanone and methylmethylate. There was no obvious relationship between absorbency and dielectric constant of the liquids being absorbed by poly(AMPS-iMz-co-MMA) and poly(AMPS-iMz-co-BMA) gels.The mechanism of superabsorbency for water and a series of organic liquids of co-polymeric gels based on AMPS-based ionic liquids were investigated. It was suggested that the reasons of superabsorbency for organic liquids were compatibility of macromolecular chains and the solvents, and the ionic liquids being completely made of ions.By using chloramphenicol as a model drug, uploading of water insoluble drugs on the xerogels of Poly(AMPS-TEA-co-AAm) was investigated by swelling the xerogel of Poly(AMPS-TEA-co-AAm) in the drug solution followed by removing the solvent to give drug-polymer conjugate using water and alcohols as a solvent, respectively.. The results showed that there was no obviously difference between absorbency in pure solvents and chloramphenicol solutions; and chloramphenicol concentration of the solutions has no influence on the absorbency. The drug loading capacity was decided by the concentration of chloramphenicol in the solutions.The drug-polymer conjugate was characterized with XRD, and the results showed that chloramphenicol was molecularly dispersed in the networks of the gels if the drug uploading was low; and chloramphenicol was crystal in the networks of the gels if the drug uploading was high.The chloramphenicol release from the xerogel of Poly(AMPS-TEA-co-AAm) was investigated in distilled water, physiological saline, and phosphate buffer solution (PBS). The results showed the release process of chloramphenicol included swelling of the xerogel, dissolution of the drug in water, and diffusion of the drug from the gels to the swelling media. The xerogel of drug-polymer conjugate swelled quickly in distilled water, physiological saline, and PBS; and the absorbency for the swelling media was decided by the drug uploading content. In distilled water, physiological saline, and PBS, the drug release ratio was40-90%and did not change after60-120min release. For more drug uploaded onto the xerogel, the drug release ratio was less.更多还原