Plastic and polymeric products are now being a part of our life and living without them is almost beyond thoughts. Plastic products got popularized and widely being accepted because of many reasons mainly light in weight, moldability in any shape, non-corrosive in nature, variety of colors, save the use of plant woods for house hold furniture and above all reusability etc.
Plastics are polymeric in nature, so in general inert in nature and suppose to cause no intracellular reachability and reactivity. The applications of plastic are rapidly increasing all over the world. Glance of their usages pattern in daily life indicates that we are approximately surrounded by 70-80% of them ranging from packaging materials, automobiles, kitchenware and children toys to the components of the designed products, aircrafts or the biomedical devices.
Plastics are used in a variety of other consumer and industrial products viz.textile, fibers, packaging, paints, automobiles, alternate building materials etc. Due to their versatile properties, plastics are also used in the electronics such as television, refrigerators, air conditioners, agricultures etc. In hospital, plastic medical devices are being used for storage and transfusion of life saving fluids, syringes, blood bags, biomedical implants, tubing and heart valves for the cardiac patients.
In the present scenario, we find the plastic usage pattern such as in various sectors. The 33% of plastic is being used for the packaging purpose, 20% in building construction, 10% in electrical and electronic items, 7% in automobiles, 5% in agriculture and 25% in the other sectors such as medical and leisure. Plastic use is dominated by single use or short term use, and at the same time most plastics are extremely persistent in the environment.
Plastics are important in our society and offer many benefits for human health and the environment, for instance.‖1, 2
Plastic packaging protects food and goods from getting wasted and/or contaminated and thereby saves resources.
The light weight packaging material saves fuel and decreases emissions during transportation.
Plastic water supply systems and storage containers/tanks provide clean water.
Light plastic materials in cars and aircraft save fuel and decreases emissions.
Plastic protective clothing and safety equipment (e.g. fire proof materials, helmets, air bags) protects from injury.
Plastic products for medical applications are very important and contribute to improved heath (e.g. blood pouches, tubings, disposable syringes, prosthesis).
The plastic industries in India started with the introduction of products like-cellulose acetate, acrylics and vinyl. The newer plastics, such as polyethylene, polypropylene, polystyrene, polycarbonate, polymethyl methacrylate, polyurethane, polyester and silicones joined polystyrene and PVC in wide applications. Plastics have increasingly provided the desired performance characteristics that fulfill consumer requirements at all levels.
They are used in such a wide range of applications because they are capable of offering desired properties that offer consumer benefits unsurpassed by any other material. More recently, because of a better understanding of the importance of surface, avoidance of contamination, and control of molecular weight and molecular weight distribution, the use of synthetic polymers in the biomedical sciences is increasing.
Polymers are viewed as important biomedical materials for a number of reasons, some of which appear contradictory-but only because of different uses require different properties. Some of the important properties are the ability to tailor make structures, surface control, strength, flexibility, rigidity, inertness/reactivity, lightweight, ease of fabrication, ability to achieve a high degree of purity, compatibility, and the ability of some of them to withstand long term exposure to the human body a truly hostile environment. Surface hydrophobicity / hydrophilicity, presence/absence of ionic groups, chemical and physical surface are all important considerations as one design a material for a specific application. In 1997, Dow introduced syndiotactic polystyrene under the trade name Questra. Targeted areas include medical, automotive, and electronic applications. Index, an ethylene-styrene interpolymer, was introduced in 1998 and is intended to compete with block copolymers such as styrene-butadiene, flexible PVC, polyurethanes and polyolefins. It is being used as a modifier for polystyrene and polyethylene.
A number of new materials have been developed because of the health fears associated with the monomer Bisphenol A, which is the comonomer for most polycarbonates. The replacement should possess similar properties to polycarbonates and also be available in large quantity and inexpensive. One material that has become available is copolymer polyester developed by Eastman. The structure for this material, Tritan, is proprietary but is believed to be based on the diol tetramethylcyclo butanediol. The ring system contributes the necessary stiffness and the methylenes supply the flexibility.‖ 3
