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ÖgeDesign of biopolymer-based advanced functional materials(Graduate School, 2022-12-16)Owing to the growing environmental interest, the use of renewable vinyl compounds, multifunctional organic acids and natural raw materials has led to the development of different methods in innovative material design. Plant extracts and biopolymers have the potential to develop advanced functional materials providing an adequate balance between mechanical strength, adequate swelling ability and biodegradability. In particular, the improvements in environmental performance can be exploited with sustainable polymers, biomass from plants and biopolymers derived from renewable raw materials such as vegetable oils, starch, gelatin, cellulose or chitin. In new methodologies developed for agrochemical applications to improve ecosystem quality, the structures containing the anionic monomer itaconic acid (ITA) have found use in the removal of physical, chemical and biological pesticides. From collagen-derived natural polymers, gelatin (GLN) is an important hydrocolloidal polypeptide for biomedical applications because it has a number of attractive advantages such as renewable character, low cost, excellent biocompatibility/biodegradability, cell adhesive structure and various functional groups for labeling and/or targeting groups and chemical modifications. The research carried out in this thesis is centered around the design of advanced functional materials based on biopolymer and carbohydrate-derived aliphatic dicarboxylic acid. Two synthesis groups were designed for the preparation of anionically modified gelatin containing Semi-IPN hybrid materials. In the first part of the experimental study, the aim was to conduct the preparation of a series of anionic copolymer hydrogels consisting non-ionic mononmer acrylamide (AAm), and anionic comomer itaconic acid (ITA) ranged between 0 and 14 mol% in the feed at a fixed crosslinker ratio. The second goal of the study was to design semi-IPN hybrid hydrogels by selecting the most appropriate anionic copolymer structure from the first synthesis group and convert it into a semi-IPN structure using various amount of Gelatin (GLN). Semi-IPN gels based on poly(acrylamide-co-itaconic acid) and a natural polymer GLN were prepared through one-step in-situ simultaneous crosslinking copolymerization. The effects of the GLN content, the incorporation of carboxyl groups of anionic comonomer ITA and amine/carboxyl functional groups of GLN on the semi-IPN hydrogel properties were investigated by varying the AAm/ITA mol ratio. The effects of changes in various physical conditions such as pH, time, GLN content and salt solutions on the physicochemical properties of gelatin-containing semi-IPNs were investigated. The solvent effect on the swelling behavior and the extent of interactions between the solvent and network chains was evaluated. The first part of the experimental work covered the synthesis of anionic copolymer poly(acrylamide/itaconic acid) (PAAm/ITAx) hydrogels containing varying amounts of the anionic comonomer ITA, ranging from 0 to 14 mol% using redox initiator pair, ammonium persulphate (APS)/N,N,N,N-tetramethylethylenediamine (TEMED) and N,N'-methylenebisacrylamide (BAAm) as a crosslinking agent. It was mainly aimed to establish a relationship between microstructure and effective charge density of anionic PAAm/ITAx hydrogels. The effective charge density turned out to be the dominant factor determining the extent of swelling. The swelling behavior of these hydrogels in water, solutions with different pH values, anionic and cationic surfactants were investigated according to the varying ITA content. A systematic discussion has been made for the variation of pH-sensitive swelling with ITA content to modulate the on-off swelling properties according to the degree of protonation/depronation of the carboxyl moieties. The mechanical properties of anionic copolymer hydrogels, both after synthesis and after swelling, were investigated with Rubber elasticity theory. Considering the equilibrium swelling theory as a simple and reliable tool for calculating the structural network parameters, this methodology has been applied for anionic PAAm/ITA hydrogels. Cationic dye removing capacities of the prepared hydrogels were determined for adsorption of Methylene blue (MB) and Methyl violet (MV) selected as model dyes. The effect of ITA content in the anionic comonomer PAAm/ITAx structure on the adsorption capacity was studied and the adsorption data were tested using the four kinetics models. Kinetic study showed that the adsorption of cationic dyes on anionic PAAm/ITA follows a gradual process with intra-particle diffusion. Besides the application of the prepared hydrogels, the objective of this work was to determine the fraction of ITA used during the synthesis, which is actively involved in the swelling process, by combining the swelling and elasticity results. Depending on the amount of anionic comonomer ITA, the change of crosslink density and effective charge density was determined. The effective charge density turned out to be the dominant factor determining the extent of swelling. In the second part of the thesis, anionically modified gelatin-based multi-responsive semi-IPN hybrid gels were prepared by free radical copolymerization of AAm and ITA in varying amounts of GLN. In order to evaluate the effect of the composition on the physicochemical and mechanical properties, the semi-IPN hybrid hydrogels in this section were designed in two different ways. While weak anionic semi-IPN hybrid hydrogels were prepared by setting AAm/ITA molar ratio as 98/2 in the copolymer network, strong anionic semi-IPN hybrid hydrogels with AAm/ITA molar ratio of 95/5 were prepared to understand the extent of interaction between ITA and GLN parts. In order to observe the GLN effect in both structures, the GLN concentration was changed between 0% and 0.750% (w/v). Semi-IPN hybrid hydrogels were prepared in-situ by first copolymerizing and crosslinking AAm and ITA in the presence of various amounts of GLN using redox initiator pair, APS/TEMED, and BAAm as a crosslinking agent. The effects of changing the GLN content, thus changing the amine/carboxyl functional groups of GLN and incorporating the carboxyl groups of the anionic comonomer ITA into the semi-IPN structure on the swelling behavior, elasticity and physical properties of poly(acrylamide-co-itaconic acid)/gelatin (PAAm/ITA-GLN) hydrogels were investigated. To investigate the effect of gelatin content on the swelling and thermal behavior, gelatin-free anionic copolymeric hydrogels were also prepared as in the first part of the experimental study. Blank copolymer PAAm/ITA hydrogel and its hybrid with GLN were characterized using Fourier transform infrared spectroscopy, X-ray diffractometry, and thermogravimetric analysis. The morphologies of the anionic gel networks were characterized using Scanning electron microscope. The uniaxial compression tests were performed after preparation of hydrogels and after their equilibrium swelling in water. Comparable differences in the swelling properties and elasticity were observed as a result of variation in GLN concentration in the semi-IPN hybrid structure. The composition effect results from the interactions between the functional groups in semi-IPN hybrid network; −CONH2 of AAm, –COOH of ITA, -OH and −NH2 of GLN. The thermal gravimetric analysis (TGA) revealed that the semi-IPN hybrid hydrogels have a higher thermal stability than the conventional copolymer PAAm/ITA hydrogel. Maximum degradation temperatures of semi-IPN hybrid hyfrogels increased with addition of GLN to PAAm/ITA network, and thermal stability was increased with high GLN content compared to other compositions. The uniaxial compression testing indicated that there is a close relationship between the GLN content and the resulting elastic properties as well as the swelling of hybrid gels. Addition of GLN to the semi-IPN hybrid structure in desired ITA content significantly affected the swelling degree and elasticity depending on the extent of interaction between the carboxyl groups of anionic comonomer ITA, hydroxyl groups and the primary amino groups of GLN. The equilibrium swelling of semi-IPN hybrid gels was studied in deionized water as a function of the GLN content. For strongly anionic semi-IPN hybrid hydrogels with AAm/ITA content 95/5, the maximum equilibrium swelling was obtained at 0.225% (w/v) of GLN. The swelling first increased rapidly with increasing GLN concentration, but then a rapid decrease in the swelling of the hybrid gels was observed. For weakly anionic semi-IPN hybrid hydrogels with AAm/ITA content 98/2, the equilibrium swelling increased sharply with an increase in the content of GLN until 0.600% (w/v), then the swelling ratio slightly decreases with further increase in GLN. A highly hydrophilic and pH-responsive system was obtained by adding 5% mol of anionic comonomer ITA to the semi-IPN hybrid hydrogels. The pH sensitivity of the designed semi-IPN hybrid structure is due to both the carboxyl group COOH and NH2 amino groups in the side chain of GLN, as well as the dicarboxylic acid-containing ITA units that show two dissociation stages. While semi-IPN PAAm/ITA-GLN hydrogels did not swell much up to pH 4.87, their pH-sensitive swelling showed a double-step increase with the S-shaped curve around pH 4.7 and 8.0 with progressive ionization of carboxylic groups. All semi-IPN hybrid hydrogels displayed temperature-sensitive swelling behavior as well as the amount of GLN added to the hybrid structure significantly affected the swelling ratio. The swelling kinetics in NaNO3 solutions proceeds by Fickian diffusion and Schott's pseudo-second order model can be effectively used to evaluate swelling kinetics. Swelling tendency in various solvents; n-pentane, n-hexane, THF, acetonitrile, chloroform, acetone, ethylacetate, dimethyl formamide, methanol, cyclohexanol, 1,4-dioxane, DMSO, ethanol, 2-propanol, and toluene showed that semi-IPN hybrid hydrogels have the highest swelling in n-hexane and the lowest in cyclohexanol. Salt-sensitive swelling in Hofmeister salts revealed that semi-IPNs tended to swell more in NaAc solution, whereas they tended to swell less in NaNO3 and NaSCN solutions. The ability of semi-IPN hybrid hydrogels to adsorb cationic dyes MB and MG from aqueous solutions was investigated as a function of GLN content and it was found that GLN-based semi-IPN hybrid gels could be a good adsorbent for the removal of cationic dyes from the contaminated waters. With the method used in this thesis, a simple and effective approach to the design of chemically cross-linked protein-based semi-IPN hybrid hydrogels for dye removal from wastewater was presented, and thermodynamically network parameters were calculated. Keywords: Gelatin, itaconic acid, acrylamide, elasticity, swelling
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ÖgeYakın kızılötesi bölgede Ag+, Cu2+ ve Hg2+ iyonlarının maskeleme ajanları ile ayrımsal ve hassas tespiti için ftalosiyanin tabanlı kimyasal sensörün geliştirilmesi(Lisansüstü Eğitim Enstitüsü, 2022-06-22)Pirol halkasında iki imino hidrojen atomu ve dört diiminoizoindol birimi tarafından oluşturulan, simetrik ve merkezindeki boşlukta birçok metal iyonunu barındırabilen makro yapılı ftalosiyanine ismi ilk olarak Profesör Reginald P. Linstead tarafından, 1933 yılında verilmiştir. 1935 yılında büyük miktarda üretilmelerinin ardından her geçen gün kullanımları artan ftalosiyanin ve türevleri; indirgeme prosesleri, katalitik oksidasyon reaksiyonları, kanser tedavisinde fotodinamik terapi ajanı, fotobaşlatıcı, lineer olmayan optik materyaller ve kimyasal sensörler gibi pek çok alanda kullanılmaktadır. Uzun ömürlü olmasının yanında fotokimyasal ve fotofiziksel olarak kararlı olan ftalosiyaninler, 18-π elektronik sistemine sahip olması sebebiyle görünür bölgede şiddetli absorpsiyon ve emisyona sahiptir. Belirli özelliklere sahip farklı ligantlar ile ftalosiyaninler, periferal ve periferal olmayan konumlarından çeşitlendirilebilir. Benzer bir yaklaşım, merkezindeki metale müdahale ile oksidasyon/indirgeme potansiyeli ve akım değerleri değiştirilerek de gerçekleştirilebilir. Çevre ve insan sağlığına zararları nedeniyle ağır geçiş metallerinin tayini çok önemlidir. Bu metaller arasında; gümüş (I) (Ag+), bakır (II) (Cu2+) ve cıva (II) (Hg2+), böbrek, karaciğer, sinir sistemi vb. üzerindeki yıkıcı etkileri nedeniyle hassas tespit için en dikkat edilmesi gerekenlerdir. Tüm geçiş metalleri arasında en yüksek termal ve elektriksel iletkenliğe sahip olan gümüş, insan vücuduna mukoza zarları, gastrointestinal sistem, cilt lezyonları ve akciğerler yoluyla giriş yapabilir ve bu durum argyria olarak bilinmektedir. Alkali pillerde, mücevheratlarda, aynalarda ve elektrikli aletlerde birçok kullanımı olan gümüşe uzun süre maruziyet sonucu anemi, kalp sorunları ve enzimatik sorunlar gerçekleşmektedir. Bakır metali; borular, vanalar ve bağlantı parçalarının kaplanabilmesinde, alaşımlarda ve yüzeydeki alglerin kontrolü gibi birçok alanda yararlı işlev göstermesinin yanında, hipoglisemi, mide hastalıkları gibi insan sağlığına ve kirletici olarak çevreye ciddi derecede zararları bulunan bir ağır geçiş metalidir. Havada, toprakta ve suda bulunabilen cıva, toksisitesi nedeniyle çevre ve insan sağlığı için büyük bir tehlikedir. Klor/kostik, elektronik cihaz ve aletlerin kimyasal üretiminde kullanılması gibi avantajlarından ziyade bağışıklık sistemi, nöro sistem endokrin sistemi üzerindeki dikkat çekici toksisitesi nedeniyle cıvanın tüm ağır geçiş metalleri arasında en tehlikelisi olduğuna inanılmaktadır. Cıva vücuda girdiğinde beyinde, sinir sisteminde ve böbreklerde birçok soruna neden olabilir. Her cıva türünün farklı toksisitesi vardır, ancak nihayetinde tüm formları çevre ve insan sağlığı için sorundur. Cıva, insan vücudunun karaciğer, beyin, doku veya kemik gibi kısımlarında birikebilir. Ve bu birikim böbrek yetmezliğine, sinir sistemi sorunlarına ve hatta ölüme neden olabilir. Yukarıda belirtilen nedenlerle; bu ağır metalleri ayrımsal olarak saptamak elzemdir. Bilim insanları için uzun yıllardır Ag+, Cu2+ ve Hg2+'nın tespiti zorlu olmuştur. Atomik absorpsiyon/emisyon spektroskopisi, indüktif eşleşmiş plazma kütle spektroskopisi, elektrokimyasal yöntemler, kromatografi ve iyon seçici elektrotlar bu ağır geçiş metallerini saptamak için kullanılan birçok yöntem arasında sayılabilir. Ne yazık ki, bu geleneksel yöntemler Ag+, Cu2+ ve Hg2+'yı düşük hassasiyet ve seçicilikle tespit edebilme gibi dezavantajlarının yanında, yüksek maliyetli olması, numune hazırlama ve uygulama için zaman alması ve deneyimli bir profesyonele ihtiyaç duyması nedenleriyle oldukça zahmetlidirler. Bu nedenlerden ötürü, ağır metal tayini için hızlı ve ekonomik, algı hassasiyeti yüksek, kullanımı kolay, daha az sinyal-gürültü oranı gibi özelliklere sahip UV-Gör ve floresan gibi metotlara yüksek bir talep olduğu fark edilmiştir. Buna bağlı olarak, bu tez çalışması kapsamında UV-Gör ve floresan yöntemiyle Ag+, Cu2+ ve Hg2+ iyonlarının ayrımsal olarak analizini yapabilen, merkaptokinolin modifiyeli ftalosiyanin tabanlı yeni bir kimyasal sensör (SQZnPc) başarıyla sentezlenmiştir. Sentezlenen sensör bileşiğinin karakterizasyonu NMR, IR, MALDI-TOF gibi yöntemlerle gerçekleştirilerek yapısı aydınlatıldıktan sonra DMF çözücü ortamında Ag+, Cu2+ ve Hg2+ iyonlarının ayrımsal analizi maskeleme yöntemi kullanılarak gerçekleştirilmiştir. Ag+, Cu2+ ve Hg2+ iyonlarının her birinin ayrı ayrı ilavesi sonucu, UV-Gör spektrumunda, ftalosiyanin ünitesine ait Q bandının (710 nm) belirgin bir şekilde azaldığı ve kaymaya uğradığı gözlemlenmiştir. Metal katyonlarını (Ag+, Cu2+, Hg2+) ayrı ayrı tespit edebilmek için literatürde EDTA, KI ve NaCl gibi maskeleme ajanları kullanılmıştır. Örneğin, Lou ve arkadaşları gibi biz de bu çalışmada EDTA kullanarak Cu2+ ve Hg2+ iyonlarını maskelemiş ve Ag+ iyonları spesifik olarak tayin etmiş bulunmaktayız. Ek olarak, Cu2+'nin seçici ve hassas tayini için KI tuzu kullanılarak Ag+ ve Hg2+ iyonları maskelenmiş ve spesifik Cu2+ tayini gerçekleştirilebilmiştir. Son olarak Hg2+'nın seçici ve hassas tayini için NaCl kullanılmış ve Ag+ ve Cu2+ iyonları maskelenebilmiştir. Böylece, UV-Gör ve floresan olmak üzere çift kanallı analiz gerçekleştiren, üç metali iyonunu (Ag+, Cu2+, Hg2+) ayrı ayrı ve hassas olarak tespit edebilen SQZnPc sensörü literatüre kazandırılmıştır.
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ÖgeWhite led induced degradation of polyacrylates as a green alternative for polymer recycling(Graduate School, 2023-06-19)In today's world, plastic materials are used almost every day due to their advantageous properties. However, widespread use of plastics has resulted in serious environmental issues, such as the buildup of plastic waste and its damaging effects on ecosystems. Efforts are underway to find effective recycling methods for widely used polymers as part of the journey towards a greener and more sustainable world, aiming to reduce this dependence. The topic of enhancing the sustainability of polymers is at the forefront of the discipline of polymer science and engineering, and it includes a variety of strategies, from mechanical recycling to degradation and chemical recycling. Poly(methyl methacrylate) (PMMA) is a polymer that holds great significance within the realm of materials due to its remarkable combination of high-impact strength, optical clarity, and lightweight characteristics. Various applications of PMMA have resulted in considerable consumption and generation of noticeable amounts of waste. By 2027, it is projected that the consumption of polymers will reach a level of 4 million tons per year and as the years pass, it could further increase. Since PMMA does not have a hydrolysable main chain, depolymerization or degradation requires advanced recycling methods. These methods involve some requirements that are both economically and environmentally harmful, such as high temperatures and heavy toxic metal catalysts. Despite the challenging conditions, the research conducted contributes to polymer recycling. However, replacing these requirements with some green alternatives is highly appealing. Photochemical reactions, with advantages such as being environmentally friendly and low energy consumption, have gained attention both in industry and academia. The idea of adapting light-induced reactions to this field and using a catalyst other than metal-based catalysts, which are another environmental pollutant factor, shed light on this study. In this study, we take advantage of the efficient properties of light in the field of degradation. We present a novel approach utilizing a white LED light source and a metal-free method for the degradation of PMMA derivatives that contain halogen in the main chain. A copolymerization incorporated PMMA derivatives containing light-triggerable halogen atoms into the main chain. The Reversible Addition-Fragmentation Chain Transfer (RAFT) controlled polymerization technique was employed for the synthesis of methyl methacrylate-methyl α-chloroacrylate and methyl methacrylate-ethyl cis-3 bromoacrylate copolymers. In the presence of organodyes (metal-free catalysts) the synthesized copolymers undergo efficient degradation into low molecular weight oligomers when irradiated with visible light. This study serves as a realistic approach to polymer recycling and leading to the development of more sustainable recycling methods for polymers.
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ÖgeCalix[4]pyrrole based supramolecular polymers via orthogonal interactions(Graduate School, 2022-02-07)Supramolecular polymers are based on reversible intermolecular interactions. Rather than linking the monomers in the desired arrangement via a covalent of polymerization reaction, the monomers are designed in such a way that they self-assemble autonomously into the desired structure. The type and strength of non-covalent interactions varies, ranging from very weak Van der Waals interactions, π-π stacking, hydrogen bonding, solvophobic interactions to dipole-dipole interactions and very strong metal-ligand or ion-ion interactions. A well-known natural supramolecular system is DNA, whose unique architecture results from cooperative non-covalent interactions, such as multiple hydrogen bonds and hydrophobic interactions. By exploiting the reversibility of the interactions, materials with fascinating properties such as self-healing, shape memory and responsive behaviour can be produced. These materials have been prepared by using cationic guests and the host molecules that can interact with these guests and found various applications in energy, regenerative medicine, nanotechnology, environment and synthetic chemistry. Calix[4]pyrroles are non-conjugated tetrapyrrolic macrocycles capable of binding anions and neutral substrates in organic media via hydrogen bonding. Moreover, upon anion binding, they change their conformation from 1,3-alternate to cone conformation to facilitate the hydrogen bonding. Apart from that, cation-π interaction between appropriate cations and π-electron cloud of cone-shaped calix[4]pyrroles are also well known. Non-covalent and reversible supramolecular interactions provide functional materials within one polymer system. These specific interactions can be designated independently and simultaneously giving orthogonal self-assembly. The aim of this thesis is to synthesize and characterize supramolecular polymers based on anion recognition chemistry of calix[4]pyrroles via orthogonal self-assembly. In this thesis pyrimidinone functionalized calix[4]pyrrole derivative (UPyCP2) and a bis-carboxylate (TBAS) salt were used as host and guest molecules, respectively. Another supramolecular polymeric system was also prepared by host-guest, cation-π and van der Walls interactions that has been built from a bis-calix[4]pyrrole (BisCP) and bis-carboxylate (CTAS) as host and guest moieties, respectively. These supramolecular polymers prepared in an organic solvent and were found tho have thermo-, chemical-responsive behaviour. The above systems have been analyzed by NMR, viscosity measurements and scanninng electron microscopy.
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ÖgeSwelling dynamics and thermomechanical properties of multifunctional hybrid systems based on N-alkyl methacrylate esters(Graduate School, 2021-12-16)Increasing demand for functional polymers in applications based on smart materials has led to the need for modified synthetic tools and new ways to design advanced materials containing specific functional groups. Improved material design is possible using specific monomers with functional groups that remain proactive under polymerization conditions and can be selectively converted to other functional groups in subsequent steps. N-alkyl methacrylate-based monomers, which can be easily polymerized under mild conditions, are widely used in design of various precisely defined functional materials. Thanks to these extraordinary features of smart gels; hydrogels have many applications in processes ranging from industrial to biological. In particular, it have many uses in many areas from food industry, pharmaceutical applications, drug delivery systems, agriculture, contact lenses, sensors, tissue engineering, controlled drug release and water purification, etc. In the first part of this study, a synthesis group was designed for the preparation of n-alkyl methacrylate ester-based multifunctional hybrid systems. It was aimed to perform the synthesis of a series of n-alkyl-methacrylate estrer-based terpolymer hydrogels consisting 2-(dimethylamino)ethyl-methacrylate (DMAEMA), hydroxypropyl-methacrylate (HPMA), and glycidyl-methacrylate (GMA) using different monomer feed compositions at a fixed crosslinker ratio. The aim of the second part of this study was to successfully synthesize terpolymer cryogels using the monomers and crosslinkers in equal proportions to those synthesized in the first part and to investigate the effect of tertiary amine groups of DMAEMA and epoxy functional groups of GMA on the gel properties. In the third part of the study; the effect of the gel preparation temperature on the gel properties was investigated. For this purpose, the results obtained from the first and second part were interpreted and the terpolymer with 20 mol% HPMA, 70 mol% DMAEMA and 10 mol% GMA structure was selected, and In this part, the terpolymer gel prepared by free radical crosslinking in water at constant monomer and crosslinker concentrations was successfully synthesized by changing the polymerization temperature between -18 and 60 oC. The effect of the change in DMAEMA/GMA mol percent ratio from 80/0 to 0/80 in the terpolymer matrix on the gel properties was investigated and it was observed that the gel properties are controlled by the tertiary amino groups in the structure of DMAEMA as well as the GMA monomer. In order to evaluate the macroscopic properties of terpolymer gels, the specific structural properties of the groups in the terpolymer matrix and their physico-chemical properties that vary depending on the monomer feed composition and gel preparation temperature were investigated. In the first part of the experimental work, it is aimed to develop a new polycationic ternary gel system with different functional groups and to evaluate the scaling relationships between the network parameters and the elastic properties. Multifunctional ternary-gels based on 2-(dimethylamino)ethyl methacrylate (DMAEMA), hydroxypropyl methacrylate (HPMA) and glycidyl methacrylate (GMA) were prepared in a wide gel preparation concentration range. The resulting gels denoted as terpolymeric poly(hydroxypropyl methacrylate-co-glycidyl methacrylate-co-2-(dimethylamino)ethyl methacrylate), PHDm/Gn-Hgs, were characterized by ATR-FTIR, and TGA measurements. The thermal stability of the terpolymer hydrogels was observed to be improved with the increase in GMA content. Swelling of ternary-gels in different solvents showed that cyclohexanol was a good solvent for the present terpolymer gel system. Swelling is controlled by DMAEMA portion of terpolymers and DMAEMA-rich gels tended to swell more than GMA-rich gels and increase in GMA content increased the polymer-solvent interaction parameter. It was determined that the addition of hydrophobic GMA to the terpolymer matrix led to a significant increase in the stiffness. The increase in elastic modulus as-prepared state is not monotonic and can be thoroughly controlled by adjusting DMAEMA/GMA ratio since tertiary amine groups triggers cascading epoxy ring-opening reaction. Dependence of swelling on the gel preparation concentration as a function of solvent quality was examined. A good solvent prediction indicated a crossover between entanglement-dominated case and strongly cross-linked case corresponding to low and moderate degrees of swelling. It has been observed that the reduced modulus decreased with increasing degree of swelling. The scaling relationship between the modulus and degree of swelling which indicates that ternary-hydrogels, limited to weak stretching regime, obey Gaussian statistics. In the second part of the experimental work, pH/thermo-responsive cationic terpolymer cryogels were successfully prepared by varying the feeding DMAEMA/GMA mol ratio. Terpolymer cryogels with different DMAEMA/GMA ratio have been extensively characterized with ATR-FTIR, X-ray diffraction analysis (XRD) and TGA measurements. The presence of GMA imparts hydrophobic character that reduces the swelling and provides additional crosslinks leading to a significant increase in the flexibility. Reducing the polymerization temperature below the freezing point of the solvent resulted in harder and non-brittle cryogels. With the increase in the amount of DMAEMA in the terpolymer matrix, the pH-dependent transition point was found to be 7.7. The water transport was strongly affected by incorporation of hydrophobic component GMA and protonation of amine functional groups. The swelling mechanism was shifted from anomalous to diffusion controlled with increasing GMA and overall swelling processes followed Schott second order dynamic equation. It was observed that lower equilibrium volume swelling at constant temperature was achieved by increasing GMA content of the terpolymers. In low temperature range, while DMAEMA-rich terpolymer gels were swollen, swelling decreased significantly when the gels were enriched in GMA. A significant difference was observed in salt-sensitive swelling in dilute salt solution, which is controlled by the amount of DMAEMA in terpolymer structure. This part of the work is important in that it provides new ideas for the design of (meth)acrylate ester-based cationic terpolymer cryogels and explains the relationship between the gel matrix and their specific swelling behavior. From the first and second part of the experimental study, the terpolymer PHDG structure containing 10% mol of GMA, 70% mol% of DMAEMA and 20 mol% of HPMA was selected and an attempt was made to establish a relationship between the the gel preparation temperature and the elasticity as well as pH/temperature sensitivity of n-alkyl methacrylate ester-based cationic gels. In the third part of the experimental study, the gel preparation temperature Tprep was changed and terpolymer gels were prepared at -18, 1, 5, 8, 24, and 60 oC. The structure and physical properties of ternary gels was fully characterized using TGA, ATR-FTIR and XRD. Tprep has been shown to be an effective independent variable to adjust both macroscopic and microscopic properties of ternary gels as desired. The dependence of the swelling and compressive elasticity on the gelation temperature was investigated and it was determined that terpolymer gels synthesized at 5 °C showed maximum swelling capacity. A significant change in the elastic modulus was observed as Tprep decreased from 60°C to -18°C. Terpolymer gels showed pH-sensitive swelling characteristic of cationic DMAEMA monomer and exhibited high swelling ratio in acidic solutions induced by the electrostatic repulsion between quaternary amine groups. It was observed that the swelling ratio decreased due to hydrophobic effect of the alkyls when environmental pH is higher than 7.7. Regardless of Tprep, the gels gradually contracted as the swelling temperature increased from 25°C to 75°C. The effectiveness of terpolymer gels to remove the anionic dye Methyl Orange from aqueous solution was tested and the results showed that the terpolymer gels prepared under low temperature conditions were promising for removing anionic dyes from wastewater. The adsorption was spontaneous and found to be a multistep process with the surface adsorption followed by the intraparticle diffusion. The results obtained will assist in the design of n-alkyl methacrylate ester-based ternary gels as an effective adsorbent for dye removal from wastewater and pharmaceutical preparations.