Theoretical investigation on multilayer nanocomposite

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Theoretical Investigation of Nanocomposites1Theoretical Investigation of NanocompositesAuthorProfessorUniversityCity, StateDate
Theoretical Investigation of Nanocomposites2Theoretical Investigation of NanocompositesAbstractNew technologies in materials science and engineering continue to be made possible bythe development of new materials, through innovation in combining materials differentcomponents whose properties are already known. Hydrogels refer to gel materials with thecapacity to absorb large quantities of water, as they are composed of networks of polymericmaterials with an abundance of polar groups in polar groups to form 3D structures that are notdeformed. These characteristics give hydrogels their hydrophilic nature that leads to their abilityto absorb water, while they remain insoluble.A polymer hydrogel can be made by combining the hydrogel properties withnanoparticles like metals, metal oxides, non-metals, and other materials like polymeric moieties.The polymeric hydrogel structural network formed between these polymeric hydrogels andnanoparticles is so well combined that the material has a superiority of functionality to the othermaterials used for the same applications. The supreme functionality is derived from the materialhaving an increased advantage of mechanical capabilities that allow the material to swell anddeswell. The material also has a super advantage of increased sensitivity to stimuli responsesystems to a variety of environments including pH, solvents, light, solutes, electric field, andeven temperature. A close analysis into the stimuli response of temperature and different aspectsrelated to the differences in thermal environment has led to the conclusion that the materialexhibits interesting inferences regarding the thermal properties of polymer hydrogels reinforceswith nanocomposites(Vashist, Gupta, and Ahmad, 2014, p. 147). These materials are thus usedin different fields in medical chemistry, such as drug delivery, catalysts and nano-medicine.
Theoretical Investigation of Nanocomposites3Polymers of hydrogels are continually being produced for different purposes, allowingthem to be either synthetic or natural, and this is made possible by cross linking their monomersthrough covalent bonding or electrostatic forces. The new technologies have made it possible forexperts to use several polymers to make up one type of hydrogel materials. These materials havefound immense uses and applications in the modern world, especially in the world ofpharmaceuticals and in the making of pesticides. An example of a hydrogel material is thesynthetic polyacrylamide (PAAm) which is a hydrophilic polymer material with a commendablemechanical strength and a high swellability of up to 90%. This material has been greatly utilizedin the world of pharmaceuticals as a drug delivery system because it enables drug release in thesame rate as the rate of degradation of the polymer(Bauera, Glasela, Hartmannaa, Langgutha,and Hinterwaldner, 2009, p. 521) This is because the material is highly sensitive to fluctuationsin pH and temperature.IntroductionSince hydrogels have the ability to swell when they absorb water and store the fluidwithin their structure, they have a physical nature of being soft when dry but having the ability togreatly expand in and exhibit extensive volume changes to store the fluid within their structure.The network of polymers is made from a network of non-covalent crosslinks that are crosslinkedbetween the component elements making up the material. These strong covalent crosslinksenable the material to have synthesized beneficial physical, mechanical and thermodynamicproperties which can appear fabricated to elicit significant swelling and the physical andmechanical properties of the polymer hydrogel, such as modulus strength of the material toprevent it from fracturing prematurely during swelling (Kutvonen, Rossi, Puisto, Rostedt, andAla-Nissila, 2012, p. 21). The structural properties of the material thus enable it to have the
Theoretical Investigation of Nanocomposites4middle of the structure to act a muscle whose ends are hard, tough, and responsive to thermalenvironments to absorb fluids into their mechanical supports. It is these properties of hydrogelsthat result in the desirable chemical, physical and biological properties that make the material thebest material for its use in medical science. Naturally, the material is naturally crosslinked toform 3D polymer networks that can store the fluid in between hollow part of their structure andthus expanding as it absorbs that fluid. While the materials can greatly increase in their size andundergo large deformations in their bodies and size when absorbing fluids, the materials arelargely insoluble in these fluids (Jordan, Jacob, Tannenbaum, Sharaf, and Jasiuk, 2007, p. 4).This is made possible by the presence of hydrophilic property groups within the structure of theitems such as the carboxyl, amido, hydroxyl, and amino groups.The degree of swelling for these materials is dependent on the components that existwithin the chains of the polymers. This is also greatly impacted by the density and concentrationof the nanoparticles and the crosslink connections of the network which allow the network ofpolymers to absorb and hold water within its structure(Rose, Prevoteau, Elziere, Hourdet,Marcellan, and Leibler, 2014, p. 384).This leads to the creation of a naturally porous structure ofthe material, such that the consistency of the material becomes elastic and soft. This promotesthe structure of the material during swelling to have very low tension while it interacts with thefluids. Thus the physical properties of polymer hydrogels reflect those biomaterials and tissues inthe medical chemistry and the pharmaceutical field. The nanocomposites of silica are covalentlymobilized into the 3D structures, thus promoting the enhancement of the structure of thematerial(Tjong, 2006, p 91). Since the structural components are what make the materialapplicable for its applications, the incorporation of nanocomposites like silica which further
Theoretical Investigation of Nanocomposites5enhance the structure of the material to give the polymer hydrogels reinforced with silicananocomposites promoting the advancement of their mechanical and thermal properties.The biggest advantage of combining the properties of two materials is to make a singlemedium that combines the structural, mechanical, and chemical properties of the compositematerials and eliminate the weaknesses to the optimum. This is yet another positive seen in thepolymer hydrogels that are reinforced with nanocomposites. This is because the mixture of thesecomposites demonstrates a synergistic level of property enhancement in this material for each ofthe components that is represented in the medium(Xia, Xie, Ju, Wang, Chen, and Chu, 2013, p.3226).For instance, the mechanical strength of polymer hydrogels reinforced withnanocomposites exhibits a commendable mechanical strength that is better than that of othermaterials used drug delivery systems, while at the same time significantly reducing theaggregation of the different nanoparticles within the medium(Münstedt and Triebel, 2011, p.202)This combination thus offers an opportunity of mutual benefits of the individualcomponents to be incorporated into one medium and decreasing the negative impacts.The material also has the ability to swell and shrink proportionate to the levels ofdifferent variables considered in the fields of medical chemistry. This implies that the mediumhas stimuli responsive systems for functions like pH, solvents, light, solutes, electric field, andeven temperature(Prado-Gotor, Lopez-Perez, Martin, Cabrera-Escribano, and Franconetti, 2014,p. 79).This property has continued to diversify their use into other fields like in the manufactureof appliance and consumer products as they exhibit a varying array in properties when applied invarying ratios with the bulk materials used. This has contributed to the limitation and regulationof the use of these materials in several countries for safety reasons(Wong and Bollampally,
Theoretical Investigation of Nanocomposites62009, p. 3399).They are thus able to help the hydrogel properties to decrease their harmfulhealth effect as they pose great environmental and health risks.They also offer an advantage of superiority in mechanical strength. Polymer hydrogelsreinforced with nanoparticles display a network of the polymer component with smallerconnections of nanoparticles so the material exhibits mechanical abilities that promote thehydrophilia exhibited by hydrogels. The network of joint polymers is able to provide the materialwith stability to hold the water absorbed by the material in place within the structure of thematerial. This thus gives the hydrogel material the required amount of rigidity to expand whileabsorbing water proportionately with other stimuli(Blumm and Opfermann, 2012, p.517).Thehydrogels exhibit mechanical capabilities that enable the material to undergo an immense levelof deformations when placed in different conditions. This thus poses as another great advantageof the material, when compared with other materials used in the field today which cannot exhibitthe level of elasticity exhibited by polymer hydrogels(Weidenfeller, Hofer, and Schilling, 2004,p. 425).Polymer hydrogels exhibit immense levels of mechanical resilience and stability as seenin their deformation when they swell and deflate when exposed to a variety of conditions.The material also exhibits expected characteristics of stress-strain relationships to explainthe elasticity of the hydrogel material as it absorbs the fluid(Fu, Feng, Lauke, and Mai, 2008,p.937).The strain levels of hydrogels are remarkably high, enabling the material to expandproportionately to the conditions the material is placed in. This is all achieved in accordance withthe proportionality rate of all the stimuli response rates of the material. The stress-straincharacteristics of polymer hydrogels can be used to explain the swellability and mechanicalaspects of the material from the aspects of uniaxial forces. The materials are known to have theability to deform elastically up to a strain level of 250% proportionately with the mechanical
Theoretical Investigation of Nanocomposites7environments and conditions exerted on the material(Lee, Park, Kim, Lee, and Yoon, 2006, p.727)Uniaxial stress conditions signify that the polymer hydrogel materials exhibits a stressstrain relationship that is non-linear, such as that exhibited by elastic material like rubber.The advantage of the material of stimuli response specifically to temperature alsopresents interests in the thermal response of polymer hydrogels reinforced with composites,proving that the merge between the components presents immense opportunities in the thermalproperties of these materials. The materials present opportunities for research and developmentin thermal aspects like thermal mechanical analysis, calorimetry, and thermo-gravimetry as theseaspects provide clarity regarding some important detail characteristics of the material(Song, etal., 2012, p. 17136)These characteristics include the polymorphism, stability and glass transitionabilities of the materials. These properties are important for pharmaceutical purposes since theyare properties tested for in stability quality control tests of medical and pharmaceutical products.Giving the polymer hydrogels silica nanocomposites reinforcement as in the case of silicananoparticle- reinforced poly (acrylamide) nanocomposites hydrogel (pAAM)gives the materialyet another set of covalent crosslinks within the structure of the material. These extra bondsredefine the structure of the material, giving it more mechanical capabilities to hold fluids withinits structure and swell and expand in large proportions. It also enables the material to be sensitiveto different thermal environments to give the material thermal properties that are unique andappropriate for the applications of this material in the industry. The concentration of thenanoparticles within the material medium and the size of the media however affects theproperties of the hydrogen and how the material responds to the different environments(Tanaka,Montanari, and Mulhaupt , 2004, p. 777). This is because it alters the distribution of the bondswithin the structure of the hydrogen polymers and also the structural arrangement and
Theoretical Investigation of Nanocomposites8distribution of the polymer network and the nanocomposites within this structure. Since thechemical and thermal properties of the material is attributed to the structural arrangement andpositioning of the different elements within the material, the concentration of the differentelements impacts the properties of the material. The trend is also similar in the analysis of thespecific thermal and mechanical properties necessary for the applications of the material in theindustry. This has been clearly demonstrated in properties like the elastic modulus which affectsthe materials ability to deform elastically, as well as the thermal diffusivity of the material(Wang and Zhu, 2011, p. 1424).Thus the material pAAM material with a few nanoparticlesdistributed within the structure of the material limits the ability of the materials to swell anddeswell as is expected.Due to the effect of the reinforced nanocomposites and the impact of their covalent bondson the structure of composite materials, the rate of elastic deformations experienced by enforcespolymer hydrogels than that of neat hydrogels. This phenomenon is an account of the effect ofthe non-covalent links on the stricter of the network of polymer bonds, restricting them formexpanding to the larges possible stretching that their structure can allow them so as to hold thefluid within the structure. The structure thus attempts to expand and swell, although the impactof the strong covalent bonds of the nanoparticles on the bonds of the polymer and thus restrictingexpansion and extension of the material to a controllable state(Lu and Mi, 2005, p. 841).This isyet another great advantage of these materials with regard to the mechanical and thermalproperties of the material, as this restriction allows for a proportionate expansion of the material,reducing the non-linearity of the stress and strain relationship of this material. This then tamesthe unpredictability of the response of the material when in specific environment, allowing thematerial to be appropriate for the different uses when the properties of reinforced
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