2011 YÜksek lisans tez özetleri

The Preparation And Characterization Of Interpenetrated Network Gels Containing Biopolymer

In this study, CS PDMAM semi-IPN hydrogels have been synthesized from chitosan (CS) natural polymer and N,N-dimethylacrylamide (DMAM). The polymerization reactions have been performed in the solution of chitosan of (1 w/v %) in aqueous acetic acid 2 v/v % by polymerizing DMAM monomer (0.2, 0.3 and 0.36 M) at 40 ^oC for 24 hours by using of ammonium persulfate (APS) and N,N,N’,N’-tetramethylethylenediamine (TEMED) as initiaitor and accelerator, respectively, in the presence of N,N’-methylenebisacrylamide (NMBA) as crosslinker. NMBA was used in the amount of 1, 2, and 3 mol % of DMAM monomer amount.

Swelling behavior of CS PDMAM semi-IPN hydrogels depending on pH, and the effects of crosslinker and DMAM concentration on the swelling have been investigated, determining the equilibrium swelling values (Q) of CS PDMAM semi-IPN hydrogels at 25 ^oC, in both distilled water and in buffer solutions (pH=2.2, 4.1, 7.0 and 10.0) with constant ionic intensity (I= 0.08 M). Chitosan films shows a bending behavior in electric field depending on the magnitude of electric field and ionic charge content of gel as it is responsive to pH due to its cationic structure, and electric field sensitivity of CS PDMAM semi-IPN gels was also examined. Structural and thermal characterization of CS PDMAM semi-IPN gels have been performed by FTIR, XRD and DSC methods.

It has been found out that the equilibrium swelling values of CS PDMAM semi-IPN hydrogels decrease with the increase in swelling environment’ s pH, the concentrations of DMAM monomer and NMBA crosslinker. Maximum swelling values were observed in the solutions with pH of 2.2 and 4.1.

T_g values of PDMAM homopolymer and CS PDMAM semi-IPN gels were determined as 135.6 ^oC and 135.9 ^oC-127.6 ^oC, respectively.

Although the response rate of CS DMAM gel films to electric field at 6V decreased with the increase of film thickness and monomer concentration due to decrease in ionic charge density of gels, their final bending angles under electric field were nearly the same. 

 

BULAK Esra

Danışman : Yard. Doç. Dr. Işıl ACAR

Anabilim Dalı : Kimya Mühendisliği

Programı : Kimyasal Teknolojiler

Mezuniyet Yılı : 2011

Tez Savunma Jürisi : Yard. Doç. Dr. Işıl ACAR

Prof. Dr. Saadet PABUCCUOĞLU

Prof. Dr. Tuncer ERCİYES

Doç. Dr. Gamze GÜÇLÜ

Doç. Dr. Tülin Banu İYİM