Study On Preparation And Properties Of Chitosan Modified Denture Resin Base

Objective:By chemical grafting method of denture polymethyl methacrylate (PMMA) weresurface modified base and Resin base surface immobilized chitosan films wereprepared, chitosan and PMMA base solid combination, slight swelling in water. Asthe research has laid the theoretical foundation of antibacterial function of the denturebase.Methods:By taking on1,6-hexamethylene diamine in n-propyl alcohol after a certaintime,several circular PMMA test were placed in glutaraldehyde solution for4h,deionized water washing several times, a surface film casting2%chitosan acetic acidsolution in the PMMA trial, dry sealed.Experimental group according to differentphases of the experiment, the unmodified PMMA specimen into group A (controlgroup), and specimen hexamethylenediamine after reaction was group B (ammoniasolution), and glutaraldehyde reaction specimens for group C, chitosan membranesurface of specimens for group D (grafting group). The naked eye observation of A,D two groups of specimens before and after the color and surface morphology, opticalperformance comparison of PMMA. The film on PMMA surface directly coatedchitosan acetic acid solution, as the group E specimens, D, E two groups of specimenssoaked in7days of artificial saliva, were observed in D, E two groups of chitosan andPMMA adhesion effect shell parts. In order to detect the influence of glutaraldehydeon grafting film, the film forming process,2%chitosan acetic acid solution withglutaraldehyde preparation sample as group F.D and F two groups of specimens wereobserved in artificial saliva immersion. By scanning electron microscopy (SEM) wasobserved in the D group the specimen surface and section morphology. By X-ray photoelectron spectroscopy (XPS) for elemental analysis of A, B, C, D four groups ofspecimens. In order to detect the changes of swelling and chitosan film absorptionoccurs, swelling of D, E two groups of specimens were compared with the rate of.Through the shape of drop recorder (DSA) determination of A group and D groupcontact angle.Results:Macroscopic observation showed that A group specimen surface and uniformcolor, pink and group D specimen surface uneven color is nebulously with opticalperformance. The D and E two groups of specimens soaked in artificial saliva.Egroups of specimens for10minutes to see the edge of a film with PMMA matrixseparation, while D group specimens after7days soaking still firmly attached to thePMMA substrate. D groups of specimens of chitosan films immersed in artificialsaliva and no shedding and F group of chitosan film off. Scanning electronmicroscopy showed that D group of chitosan film surface smooth, dense and uniform,not brokenly, porely, completely coverage, fault display chitosan membrane internaldense and uniform surface, no bubbles, neat, chitosan combined with PMMA resinand the interface without fracture, the film thickness is about8μm. X-rayphotoelectron spectroscopy results show D group specimen surface in the presence ofC, N, O elements, three elements than with the chitosan molecules in the element ratio.It proves that the modified method of chitosan grafted onto the PMMA surface bygrafting.The test results show that the swelling rate of group E was390.9%±0.751swelling rate, swelling significantly; group D swelling rate was42.9%±0.085, onlyslight swelling.By t test statistical analysis and comparison, D group than in E groupthe swelling rate had significant difference (n=12, P <0.01). Contact anglemeasurement results showed that A group specimens contact angle was105.91±8.39°, D groups of specimens of contact angle of80.89±8.17°.T test was used instatistical analysis, the contact angle of D group and A group were significativelydifferent (n=6, P <0.01), surface modification of PMMA hydrophilic wassignificantly improved latter.Conclusions:By chemical grafting modification, chitosan was immobilized to the surface of PMMA successfully. Adding crosslinking agent glutaraldehyde to the chitosan aceticacid solution reduced combination between chitosan and PMMA surface. Chitosanfilms supported the water only slight swelling.PMMA surface hydrophilicity ofchitosan graft significantly improved.