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The future of plastic materials is promising, as researchers within the engineering community have discovered a wide range of applications in which the unique and valuable properties of polymers are well suited for. This article will examine the specific characteristics of polymers that have proven to be beneficial for smart surfaces.
Plastic, which is derived from polymer materials, has become an integral part of our global society. To this end, polymers can be found in a wide variety of products ranging from food and drink containers to refrigerator insulin and tubing. The distinctive properties of plastic materials have significantly extended their traditional applications to a number of smart and intelligent materials, sensors, high-temperature organic materials, and multi-component hybrid systems.
Unique Polymer Properties
In addition to the hydrophobicity and electronically responsive characteristics of polymers, both of which will be described in more detail below, many smart materials companies have utilized polymers for a wide variety of purposes. Some of the advantages noted by the Austrian company Smart Plastics, for example, include the high chemical and physical resistance of the material that can be achieved following the application of specific topcoats, cost-effective design abilities that can be met with a high degree of freedom during the design process and a significantly lower requirement of plastic products for each part that is produced.
There are numerous properties that support the application of polymer materials for smart surfaces. Both the micro- and nanostructure of the surface of polymer materials, for example, can strongly influence the properties of polymers when incorporated into smart surfaces. More specifically, microstructured, rough surfaces can adjust the surface chemistry of polymers in terms of their wetting capabilities, as well as their cell attachment and spreading behavior.
When developing smart materials that will be utilized within the health industry, it is crucial for these materials to avoid contact with the potential contamination of dirt, bacteria, and viruses. Since the presence of water can often attract these unwanted microorganisms, hydrophobic materials are often of interest when developing smart medical products. To this end, polymers on their own, as well as those that have been enhanced with inorganic particles and/or metal oxides, have demonstrated both rapid cleaning and super drying capabilities, both of which have been found to significantly improve the quality of the product’s overall surface.
Like many other smart synthetic materials, smart surfaces should be capable of responding to external and/or internal stimuli and should subsequently adjust their properties on demand. Within the scientific community, smart surfaces are particularly of interest to researchers developing microfluidic and “lab-on-chip” devices, controlled drug delivery systems and sensors, as well as enzyme immobilization, bioseparation, and controlled cell adhesion applications.
To this end, stimuli-responsive polymers (SRPs), which are polymer materials that respond to changes in their environment through alterations of their physical and/or chemical properties, have emerged. In addition to physicochemical changes, SRPs can also undergo conformational, self-assembly and solubility changes in response to a wide range of stimuli including temperature, pH value, light, magnetic field electricity, and water. SRPs have been constructed from several different polymers including homopolymers, graft copolymers, molecular brushes, and statistical/block copolymers.
Many polymer-based smart surfaces exhibit pH/T responsiveness variations that have been incorporated onto grafted polymer chains obtained from a solid substrate. In fact, pH/T dual-responsive behavior can even arise following the chemical alteration of polymer surfaces. With these specific material characteristics in mind, several industries that are interested in developing polymer-based multi-responsive surfaces have conducted a variety of studies on PNIPA, which is a well-known temperature-responsive polymer.
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- “Advantages” – Smart Plastics
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