| As a kind of high water absorbing and high water retaining polymer material,hydrogels have broad practical significance and application prospects in tissueengineering, biology, medicine and other fields. Hydrogels can be widely used as drugrelievers, tissue filling agent, the embedding of enzymes and artificial skin. Thisthesis mainly studies the structure, performance and drug release behavior of PAAhydrogels and PNIPAM hydrogels. First, the synthesis of two kinds hydrogels werefinished using the method of radical solution polymerization. Two differentcrosslinking agents (MBA and OVPOSS)were used. Then the structure andperformance of the hydrogels were researched, including swelling behavior and drugreleasing behavior.The structure of the PAA hydrogels and PNIPAM hydrogels were performedusing FTIR. The characterization of OVPOSS and the structure of PNIPAM hydrogelswere performed by X-ray diffraction (XRD), proving that the structure of the twocrosslinking agents (MBA and OVPOSS) existed in the hydrogels. The morphologyand the size of the hole after swelling were observed by scanning electron microscopy(SEM). The analysis of combined water and freezing water in hydrogels, and the glasstransition temperature (Tg) were studied using differential scanning calorimetry(DSC). The content of freezing water of P(MBA-co-PAA) hydrogels was higher thanP(OVPOSS-co-PAA) hydrogels, the glass transition temperature of theP(OVPOSS-co-PAA) hydrogels was higher than the P(MBA-co-PAA) hydrogels. Thethermal decomposition temperature of the two hydrogels was performed bythermogravimetry (TGA), the result showed that the thermal decompositiontemperature of the P(OVPOSS-co-PNIPAM) hydrogels was higher.The swelling behavior and potential applications in the field of drug releasing of hydrogels under different pH and temperature were also studied. Results showed thatthese two kinds hydrogels had pH sensitivity and temperature sensitivity respectively.However, as the addition of OVPOSS limited the movement of molecular chain, whenOVPOSS was used as the crosslinking agent, the swelling ratio and drug releasingrate of hydrogels decreased significantly compared with hydrogels crosslinked withMBA. |
