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Polymer Biomaterial Constructs For Regenerative Medicine and Functional Biological SystemsMeng, Linghui 26 June 2012 (has links)
No description available.
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pH Dependence of Acrylate-Derivative Polyelectrolyte PropertiesSwift, Thomas 05 July 2018 (has links)
Yes / There are many polymers formed of acrylate monomers in existence. Here we interrogate four commonly-used examples and study how their solution properties are pH dependent, or how their state of ionisation can affect their solution properties. Poly(acrylic acid) and poly(methacrylic acid) are both polyelectrolytes, with ionisable functional groups that make them stimuli responsive, changing their hydrodynamic volume. Poly(acrylamide) is a mass-produced material used in a variety of industrial applications, often with an anionic and cationic co-monomer, which dictates both its efficacy and impact on the environment. Poly(N-isopropyl acrylamide) is a thermally responsive material with applications in smart bioengineering. In solution, these materials can interact with each other due to competing hydrogen bonding interactions. However, this interpolymer complexation is dependent on both the ionisation, and the conformational state, of the polymers involved. This review focuses on the results from fluorescence tagging and turbidimetric techniques.
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Μελέτη αλληλεπιδράσεων ιόντων Cu2+ με συμπολυμερή του ακρυλικού οξέος σε υδατικό διάλυμα / Study of the interactions between Cu2 + ion with acrylic acid copolymers in aqueous mediaΤσοπελάκης, Φίλιππος 02 April 2014 (has links)
Στην εργασία αυτή προχωρήσαμε στη μελέτη της αλληλεπίδρασης των ιόντων δισθενούς χαλκού, Cu2+ με στατιστικά συμπολυμερή P(ANa-co-SSNa) του ακρυλικού οξέος, (ANa) με το στυρενοσουλφονικό οξύ (SSNa). Συντέθηκαν τα συμπολυμερή P(ANa50-co-SSNa) και P(AΝa80-co-SSNa) που περιέχουν 50 mol% και 80 mol% ακρυλικού οξέος αντίστοιχα. Τα συμπολυμερή αυτά χαρακτηρίστηκαν με φασματοσκοπία πυρηνικού μαγνητικού συντονισμού 1H NMR.
Προχωρήσαμε στην φυσικοχημική μελέτη της αλληλεπίδρασης ιόντων δισθενούς χαλκού, Cu2+, με τα συμπολυμερή P(ANa50-co-SSNa) και P(AΝa80-co-SSNa) χρησιμοποιώντας διάφορες τεχνικές όπως η θολομετρία, η ιξωδομετρία και η φασματοσκοπία UV-vis. Τα πειράματα πραγματοποιήθηκαν σε υδατικά διαλύματα, στα οποία χρησιμοποιήθηκε ως διαλύτης τρισαπιονισμένο νερό, H2O-3D. Για λόγους σύγκρισης μελετήθηκαν επίσης τα αντίστοιχα ομοπολυμερή των μονομερών που αποτελούν τα συμπολυμερή P(ANa-co-SSNa). Έτσι, πραγματοποιήθηκε φυσικοχημική μελέτη της αλληλεπίδρασης των ιόντων Cu2+ με το πολυ(ακρυλικό νάτριο), PANa, και το πολυ(στυρενοσουλφονικό νάτριο), PSSNa, αντίστοιχα.
Από την ιξωδομετρική μελέτη προέκυψε πως η εισαγωγή ιόντων χαλκού Cu2+ σε υδατικό διάλυμα πολυμερούς οδηγεί στην μείωση του ανηγμένου ιξώδους. Μάλιστα η μείωση αυτή είναι πιο δραστική καθώς αυξανεται η συγκέντρωση ιόντων Cu2+ στο διάλυμα. Αυτή η συμπεριφορά αποτελεί ένδειξη της συμπλοκοποίησης των ιόντων χαλκού, Cu2+, με τις ομάδες καρβοξυλίων του ακρυλικού οξέος (ΑΑ). Διαπιστώθηκε πως στα συμπολυμερή P(ANa-co-SSNa) τα Cu2+ συμπλοκοποιούνται με τα καρβοξύλια του ακρυλικού οξέος σε αναλογία ιόντων χαλκού προς ομάδες καρβοξυλίων ίση με 1:2.
Όσον αφορά στην μελέτη με UV-vis, ενώ στην περίπτωση του ομοπολυμερούς PSSNa δεν υπάρχει κάποια ιδιαίτερη αλληλεπίδραση τύπου συμπλόκου ένταξης μεταξύ του πολυμερούς και των ιόντων του Cu2+, στην περίπτωση του συμπολυμερούς Ρ(ΑNa50-co-SSNa), παρατηρήθηκε μετατόπιση του σήματος των ιόντων Cu2+ (από τα 800 στα 745 nm) παρουσία του συμπολυμερούς. Αυτό είναι χαρακτηριστικό του σχηματισμού συμπλόκου ένταξης μεταξύ των ιόντων του Cu2+ και των ομάδων COO- του συμπολυμερούς. / In the present work we studied the interaction of bivalent copper ions Cu2+ with random copolymers P(ANa-co-SSNa) of acrylic acid (ANa) and styrenesulfonic acid (SSNa). Two copolymers, P(ANa50-co-SSNa) and P(AΝa80-co-SSNa) with 50 mol% and 80 mol% in acrylic acid, respectively, were synthesized and characterized by neutron magnetic resonance spectroscopy, 1H NMR.
We proceeded in the physicochemical study of the interaction
of bivalent copper ions, Cu2+, with P(ANa50-co-SSNa) and P(AΝa80-co-SSNa) copolymers using techniques like turbidimetry, viscometry and UV-vis spectroscopy. The experiments were performed in aqueous media using 3D water, H2O-3D. For reasons of comparison the respective homopolymers of sodium polyacrylate, PANa, and poly(styrene sulfonate), PSSNa, were also studied.
From viscometry it was found that the introduction of copper ions in the polymer aqueous solutions leads to the decrease of the reduced viscosity. Moreover, this decrease is more pronounced as the concentration of Cu2+ increases in the solution. This behavior is indicative of the complexation between Cu2+ with the carboxylate groups of acrylic acid (ΑΑ). In the P(ANa-co-SSNa)/Cu2+ system, it was found that complexation occurs when the ratio of copper ions to carboxylates is equal to 1:2.
UV-vis spectroscopy showed that, while in the case of PSSNa homopolymer there is not strong interaction with Cu2+, in the case of the Ρ(ΑNa50-co-SSNa) copolymer, the introduction of the polymer lead to a shift of the maximum absorbance of Cu2+ (from 800 to 745 nm). This was due to the complexation of Cu2+ with the COO- groups of the copolymer.
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Poly(ethylene-co-acrylic acid) random copolymers : amphiphilic properties and self-assembly in aqueous mediumKriuchkov, Volodymyr 01 1900 (has links)
Les travaux de recherche présentés ici avaient pour objectif principal la synthèse de copolymères statistiques à base d’éthylène et d’acide acrylique (AA). Pour cela, la
déprotection des groupements esters d’un copolymère statistique précurseur, le
poly(éthylène-co-(tert-butyl)acrylate), a été effectuée par hydrolyse à l’aide d’iodure de
triméthylsilyle.
La synthèse de ce précurseur est réalisée par polymérisation catalytique en présence
d’un système à base de Palladium (Pd).
Le deuxième objectif a été d’étudier et de caractériser des polymères synthétisés à
l’état solide et en suspension colloïdale. Plusieurs copolymères précurseurs comprenant
différents pourcentages molaires en tert-butyl acrylate (4 à 12% molaires) ont été
synthétisés avec succès, puis déprotégés par hydrolyse pour obtenir des poly(éthylène-coacide
acrylique) (pE-co-AA) avec différentes compositions. Seuls les copolymères
comprenant 10% molaire ou plus de AA sont solubles dans le Tétrahydrofurane (THF) et
uniquement dans ce solvant. De telles solutions peuvent être dialysées dans l’eau, ce qui
conduit à un échange lent entre cette dernière et le THF, et l’autoassemblage du
copolymère dans l’eau peut ensuite être étudié. C’est ainsi qu’ont pu être observées des
nanoparticules stables dans le temps dont le comportement est sensible au pH et à la
température.
Les polymères synthétisés ont été caractérisés par Résonance Magnétique Nucléaire
(RMN) ainsi que par spectroscopie Infra-Rouge (IR), avant et après déprotection. Les
pourcentages molaires d’AA ont été déterminés par combinaison des résultats de RMN et
ii
de titrages conductimètriques. A l’état solide, les échantillons ont été analysés par
Calorimétrie différentielle à balayage (DSC) et par Diffraction des rayons X.
Les solutions colloïdales des polymères pE-co-AA ont été caractérisées par
Diffusion dynamique de la lumière et par la DSC-haute sensibilité. De la microscopie
électronique à transmission (TEM) a permis de visualiser la forme et la taille des
nanoparticules. / The first objective of this research is to synthesize random linear copolymers of
ethylene and acrylic acid (AA). The synthesis relies on the deprotection of the functional
groups in the copolymer’s precursor, which is represented by poly(ethylene-co-tertbutyl
acrylate). The synthesis of the precursor was realized by the catalytic approach, where
Pd-based catalytic systems are frequently utilized nowadays. The deprotection was
carried out by hydrolysis of the ester functionality using trimethylsilyl iodide agent.
The second objective is to investigate and characterize the synthesized polymers in
the bulk and in colloidal solution. A set of different precursor polymers with various
degrees of molar incorporation of tertbutyl acrylate (from 4 to 12 mol %) was
successfully synthesized and deprotected. The resulting poly(ethylene-co-acrylic acid)
copolymers were found to be soluble in tetrahydrofuran THF, when the molar
incorporation of AA reaches the value of 12 and more. This aspect gave the possibility to
study the self-assembly of this copolymer in aqueous medium by slow THF to water
exchange (dialysis). It was found that the copolymers self-assemble into nano-sized
structures and these nanoparticles remain stable in colloidal solution for extended periods
of time. Moreover, it was shown that the nanoparticles formed by the discussed
copolymer possess thermo- and pH-responsive behaviour.
The polymers synthesized were characterized by nuclear magnetic resonance
(NMR) and infrared spectroscopies (IR) before and after deprotection. The bulk samples
were analyzed by conventional differential scanning calorimetry and by X-ray diffraction
iv
technique. The molar percentages of AA were determined using a combination of NMR
and conductimetric titration. Colloidal solutions of pE-co-AA copolymers were analyzed
by dynamic light scattering and high-sensitivity differential scanning calorimetry
techniques. The nanoparticles formed were visualized and characterized by transmission
electron microscopy.
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Polymérisation radicalaire contrôlée par transfert d'iode en mode inverse (RITP) : Synthèse de copolymères amphiphiles / Reverse Iodine Transfer radical Polymerisation (RITP) : Synthesis of amphiphilic copolymersRayeroux, David 20 December 2012 (has links)
Ce travail de thèse décrit la synthèse de copolymères diblocs amphiphiles par polymérisation radicalaire contrôlée par transfert d'iode en mode inverse (RITP). Dans un premier temps, des homopolymères à base de monomères activés (styrène, acrylate de méthyle, méthacrylate de méthyle), non activés (acétate de vinyle) et fonctionnels (chlorométhylstyrène, acrylate de tert-butyle), ont été synthétisés par RITP. Des aspects tels que le contrôle des masses molaires ainsi que la fonctionnalité en iode du bout de chaîne ont été examinés. Afin de démontrer la compatibilité de la RITP avec d'autres techniques de polymérisation contrôlée/vivante (non radicalaires), le copolymère amphiphile non-ionique poly(styrène)-b-poly(2-méthyl-2-oxazoline) (PS-b-P(MOx)) a été élaboré par la voie toute iode en procédé « one-pot » en combinant de manière consécutive la RITP du styrène avec la polymérisation cationique par ouverture de cycle (CROP) de la 2-méthyl-2-oxazoline. Par ailleurs, des copolymères cationiques poly(styrène)-b-poly(chlorométhylstyrène) quaternisé avec la triéthylamine (PS-b-PCMS+) et anioniques poly(styrène)-b-poly(acide acrylique) (PS-b-PAA-) ont été synthétisés par RITP du styrène suivie de l'ITP du bloc hydrophile. Tous ces copolymères amphiphiles ont été obtenus à partir de polystyrène iodé (PS-I) de faibles masses molaires, allant de 1000 à 3000 g.mol-1, jouant le rôle de macro-amorceurs (CROP) ou de macro-agents de transfert (ITP). L'étude de l'auto-organisation en phase aqueuse de ces copolymères amphiphiles a révélé la formation de micelles pour des concentrations supérieures à la concentration d'agrégation critique (CAC) dont la valeur a été déterminée par diffusion dynamique de la lumière (DDL) et spectroscopie de fluorescence. Enfin, des résultats très prometteurs ont été obtenus dans l'utilisation d'un copolymère cationique amphiphile PS-b-PCMS+ comme agents structurants de matériaux siliciques mésoporeux nanostructurés élaborés par procédé sol-gel en milieu basique. La synthèse de ces copolymères amphiphiles ainsi que leur caractérisation physico-chimique ont mis en exergue que la RITP permet de couvrir la synthèse de différentes catégories de copolymères amphiphiles, tout en étant une technique simple à mettre en œuvre, peu couteuse et robuste. / This manuscript describes the synthesis of amphiphilic diblock copolymers by reverse iodine transfer polymerization (RITP). Firstly, homopolymers derived from activated (styrene, methyl acrylate, methyl methacrylate), non-activated (vinyl acetate) and functional monomers (chloromethylstyrene, tert-butyl acrylate) synthesized by RITP, were studied. Aspects including molecular weight control as well as iodine chain-end functionality were investigated. In order to highlight the compatibility of RITP with other living/controlled (non-radical) polymerization techniques, a poly(styrene)-b-poly(2-methyl-2-oxazoline) (PS-b-P(MOx)) non-ionic copolymer was conceived through an ‘all-iodine', ‘one-pot' process by combining successively RITP of styrene with cationic ring-opening polymerization (CROP) of 2-methyl-2-oxazoline. Besides, poly(styrene)-b-poly(chloromethylstyrene) quaternized with triethylamine (PS-b-PCMS+) cationic copolymers and poly(styrene)-b-poly(acrylic acid) (PS-b-PAA-) anionic copolymers were elaborated by RITP of styrene, followed by ITP of the hydrophilic moiety. All these amphiphilic copolymers were obtained from iodine-bearing chain-end poly(styrene) (PS-I) of low molecular weights, in the range of values of 1000 to 3000 g.mol-1, playing the role of macro-initiators (CROP) or macro-transfer agents (ITP). Studies of the self-assembly of these amphiphilic copolymers in aqueous phases revealed the formation of micelles for concentrations superior to the critical aggregation concentration (CAC). The latter value was determined by dynamic light scattering (DLS) and fluorescence spectroscopy. Moreover, highly-promising results were obtained in the use of PS-b-PCMS+ cationic copolymers as structuring agents meant for the elaboration of nanostructured, mesoporous silica-based materials through the sol-gel process in basic medium. Both the synthesis of the amphiphilic copolymers and their physico-chemical characterizations have evidenced that RITP fosters the synthesis of different categories of amphiphilic copolymers, while being a simple, cheap and robust technique.
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Desenvolvimento de hidrogéis inteligentes como meio de liberação controlada de fármaco / Development of smart hydrogels as controlled drug delivery systemsTakahashi, Suélen Harumi 18 August 2014 (has links)
O objetivo principal deste trabalho foi a formação de um material que possa responder aos estímulos pH e elétrico na liberação controlada de fármaco. Assim, hidrogéis condutores foram obtidos pela combinação do hidrogel de ácido acrílico com o polímero condutor polipirrol. O polipirrol foi eletroquimicamente polimerizado no interior do hidrogel e o material obtido (AA-PPi) conservou a propriedade de intumescimento que é característico dos hidrogéis e a eletroatividade, dos polímeros condutores. Além disso, o grau de intumescimento variou com a força iônica e pH. A liberação da safranina pelo hidrogel de AA-PPi foi estudada combinando os estímulos de pH e potencial e o resultado mais interessante foi a obtenção do perfil cuja velocidade de liberação foi constante, indicando uma cinética de ordem zero. Liberação do tipo liga-desliga foi estudada com o intuito de verificar se o AA-PPi pode ser controlado por pH e/ou potencial elétrico. Foi observado que dependendo da combinação de pH e potencial, o hidrogel pode ser controlado, por variação de pH ou de potencial elétrico. Outro hidrogel sintetizado foi o do hidrogel de AA contendo o poli(3,4-etilenodioxitiofeno):poli(estireno sulfonado), este por sua vez foi polimerizado quimicamente. Porém os resultados preliminares indicaram incompatibilidade entre os dois polímeros / The aim of this work was to obtain a material that can respond to both pH and potential stimuli for drug release. Thus, eletroactive hydrogels were synthesized by the combination of the properties of acrylic acid hydrogels with the conducting polymer polypyrrole. The polypyrrole was electrochemically polymerized into the hydrogel (AA-PPi), and the material retained the swelling properties that is characteristic of hydrogels and electroactivity of conducting polymers. Furthermore, the degree of swelling varied with the ionic strength and pH. The safranin release by AA-PPi was mensured under the combination of pH and potential stimuli and the most interesting result was obtained from the linear profile indicating a zero-order kinetics. On-off release profile was studied in order to verify if the AA-PPi can be controled by pH and/or electric potential. Depending on the combination of pH or electrochemical potential, the hydrogel had pH or electrochemical control. Other hydrogel synthesized was from AA hydrogel containing poly(3,4- ethylenedioxythiophene):polystyrene sulfonate, this, in other hand, was chemically polymerized. However, preliminary results indicate incompatibility between the two polymers
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Preparo e caracteriza??o de membranas de quitosana modificadas com poli (?cido acr?lico)Lima, Maria do Socorro Pereira de 17 November 2006 (has links)
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Previous issue date: 2006-11-17 / The aim of this study was to generate an asymmetric biocompactible and biodegradable chitosan membrane modified by the contact with a poly(acrylic acid) solution at one of its sides at room temperature and 60◦C. The pure chitosan membrane, as well as the ones treated with poly(acrylic acid) were characterized by infrared spectroscopy (FTIRATR) at angles of 39◦, 45◦ and 60◦ , swelling capacity in water, thermal analysis (TG/DTG), scanning electronic microscopy (SEM) and permeation experiments using metronidazole at 0,1% and 0,2% as a model drug. The results confirmed the presence of ionic interaction between chitosan and poly(acrylic acid) by means of a polyelectrolyte complex (PEC) formation. They also showed that such interactions were more effective at 60◦C since this temperature is above the chitosan glass transition temperature wich makes the diffusion of poly(acrylic acid) easier, and that the two treated membranes were asymmetrics, more thermically stable and less permeable in relation to metronidazole than the pure chitosan membrane / O prop?sito deste estudo foi produzir uma membrana assim?trica biocompat?vel e biodegrad?vel de quitosana modificada pelo contato com uma solu??o de poli(?cido acr?lico) em uma de suas superf?cies ? temperatura ambiente e a 60◦C. As membranas de quitosana pura, quitosana com poli(?cido acr?lico) a 25◦C e quitosana com poli(?cido acr?lico) a 60◦C foram caracterizadas por: espectroscopia no infravermelho (FTIRATR) em ?ngulos de incid?ncia de 39◦, 45◦ e 60◦, ganho de massa em ?gua, an?lise t?rmica (TG/ DTG), microscopia eletr?nica de varredura (MEV) e, ainda, atrav?s dos ensaios de permea??o in vitro utilizando como f?rmaco modelo o metronidazol em solu??o aquosa nas concentra??es de 0,1 e 0,2%. Os resultados obtidos comprovaram a exist?ncia de intera??es i?nicas entre os dois pol?meros, atrav?s da forma??o dos chamados complexos polieletrol?ticos. Tamb?m mostraram que a reticula??o foi mais efetiva a 60◦C , uma vez que essa temperatura est? acima da temperatura de transi??o v?trea da quitosana, o que facilita a difus?o do poli(?cido acr?lico) e que as membranas resultantes s?o assim?tricas, mais est?veis termicamente e menos perme?veis ao metronidazol do que a membrana de quitosana pura
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Control of the rheological properties of hydrogels made by self-assocation of amphiphilic copolymers, blocks and grafts, anionics or cationics / Contrôle des propriétés rhéologiques d'hydrogels formés par auto-assemblage de copolymères amphiphiles, à blocs et greffés, anioniques ou cationiquesLauber, Lionel 19 September 2016 (has links)
L’objectif de ce travail était de contrôler les propriétés rhéologiques de solutions aqueuses de copolymères amphiphiles. Dans l’eau, ces copolymères s’auto-associent et leurs propriétés peuvent être contrôlées en partie par leur dynamique d’échange. Il avait précédemment était montré que cette dynamique pouvait être contrôlée par le pH et la quantité d’unités acide acrylique dans des triblocs BAB (THx) où le bloc A est du poly(acide acrylique) (PAA) et les blocs B sont des copolymères statistiques (MHx) d’acrylate de n-butyle (nBA) et d’acide acrylique (AA). Tout d’abord, l’étude de l’auto-association en solution des blocs B seuls (MHx) a montré un lien fort entre leur agrégation et celle des diblocs de type BA (DHx). Cette agrégation est contrôlée par la quantité de charge des blocs B. Par la suite, des mélanges de triblocs (BAB) THx contenant différentes proportions (x) d’unités AA ont permis la formation de réseaux hybrides dont les propriétés rhéologiques sont maîtrisées par formulation plutôt que via la chimie. Des propriétés rhéologiques similaires aux triblocs BAB (THx) ont été obtenues avec des copolymères greffés possédant un squelette hydrophile PAA et des greffons B. Leurs propriétés rhéologiques sont principalement contrôlées par la structure chimique des blocs B, mais aussi par le taux de greffage. Ces copolymères greffés devraient être plus simples à obtenir à l’échelle industrielle que des triblocs. Pour finir, l’approche consistant à incorporer des unités hydrophiles dans les blocs hydrophobes de copolymères amphiphiles pour en contrôler la dynamique d’échange a été appliquée avec succès à des copolymères à base de méthacrylate de diméthylaminoéthyle et de méthacrylate de n-butyle. Leurs propriétés rhéologiques peuvent être contrôlées à nouveau par le pH, mais dans une gamme différente des polymères à base d’acide acrylique, et aussi dans une certaine mesure par la température. / The aim of this work was to control the rheological properties of aqueous solutions of amphiphilic copolymers. In water, these copolymers self-assemble and part of their properties can be controlled by their dynamic of exchange. As previously reported, the exchange dynamics can be controlled by the pH and the acrylic acid (AA) content for BAB triblock copolymers (THx) consisting of a poly(acrylic acid) (PAA) A block and two statistical B blocks (MHx) of n-butyl acryle (nBA) and AA.First, the study of the self-association of B blocks (MHx) alone showed a strong relationship between their aggregation and the one of BA diblocks (DHx). This aggregation was mainly controlled by the amount of charges within the B blocks.Then, mixtures of BAB triblocks (THx) with different contents of AA units, x, formed hybrid networks the rheological properties of which were controlled by formulation rather than chemistry.Similar rheological properties were obtained using graft copolymers consisting of a PAA hydrophilic backbone and B grafts. Their rheological properties were mainly controlled by the chemical structure of the B grafts and by the grafting density. Such graft copolymers should be easier to produce at an industrial scale than triblock copolymers.To finish, the strategy consisting of incorporating hydrophilic units inside the hydrophobic blocks of amphiphilic copolymers to control their exchange dynamics was successfully applied to copolymers made of dimethylaminoethyl methacraylate and n-butyl methacrylate. Their rheological properties were controlled by the pH on a different pH-range than the AA based polymers, and, to some extent, by the temperature.
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Synthesis and Characterization of Ethylene-Acrylic Acid Copolymers Produced under High PressureNergui, Undrakh 08 July 2009 (has links)
No description available.
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Chemical and mechanical characterization of fully degradable double-network hydrogels based on PEG and PAAWorrell, Kevin 18 May 2012 (has links)
Biodegradable hydrogels have become very promising materials for a number of biomedical applications, including tissue engineering and drug delivery. For optimal tissue engineering design, the mechanical properties of hydrogels should match those of native tissues as closely as possible because these properties are known to affect the behavior and function of cells seeded in the hydrogels. At the same time, high water-contents, large mesh sizes and well-tuned degradation rates are favorable for the controlled release of growth factors and for adequate transport of nutrients through the hydrogel during tissue regeneration. With these factors in mind, the goal of this research was to develop and investigate the behavior of injectable, biodegradable hydrogels with enhanced stiffness properties that persist even at high degrees of swelling. In order to do this, degradable functionalities were incorporated into photo-crosslinkable poly(ethylene glycol) and poly(acrylic acid) hydrogels, and these two components were used to make a series of double-network hydrogels. Synthesis of the precursor macromers, photopolymerization of the hydrogels, and structural parameters of the hydrogels were analyzed. The composition and the molecular weight between crosslinks (Mc) of the hydrogel components were varied, and the degradation, swelling, thermal and mechanical properties of the hydrogels were characterized over various time scales. These properties were compared to corresponding properties of the component single-network hydrogels.
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