Plastics

Plastics

Background

“Plastic” is the name given to a varied range of synthetic and semi-synthetic products of a process called polymerization. They are generally composed of addition polymers and may or may not contain various other substances that are meant to improve their performance or economic value. Plastics are polymers, or long chains of atoms that are bonded to one another. These chains are composed of numerous repeating molecular units, and each of the polymer chains may have several thousands of such “repeat units”. The majority of plastics are polymers of carbon and hydrogen either alone or with oxygen, nitrogen, chlorine or sulfur. The versatility and variability of the molecular structure has allowed plastics to become an indispensable part of modern life and allowed “tailoring” of the properties of the polymer to specific uses.

In general, Plastics can be classified most commonly by their “polymer backbone” (polyvinyl chloride, polyethylene, polymethyl methacrylate and other acrylics, silicones, polyurethanes, etc.). Other modes of classification for plastics include categories such as thermoplastic, thermoset, elastomer, engineering plastic, addition or condensation or polyaddition, which classify them according to the polymerization method that was used, and the glass transition temperature or Tg. Some plastics are partially crystalline in molecular structure, semi-crystalline plastics, which include polyethylene, polypropylene, poly vinyl chloride or PVC, polyamides or nylons, polyesters and some of the polyurethanes. Other plastics are completely amorphous, like polystyrene and its copolymers, poly(methyl methacrylate), and all of the jathermosets.

Historically, human beings have experimented with plastics, based on natural polymers, for many centuries. In 1839 Charles Goodyear discovered the vulcanization of rubber, creating a plastic material based on chemically modified natural polymers. Alexander Parkes created the earliest form of man made plastic, a hard but flexible transparent material called "Parkesine,” in 1855. Subsequently discoveries such as poly(vinyl chloride), polystyrene, polyethylene (polyethene), polypropylene (polypropene), polyamides (nylons), polyesters, acrylics, silicones, polyurethanes have created many varieties of plastics and have great led to great commercial success for plastics as a category.

Structure

The plastic industry includes finished plastic products as well as raw materials and plastic processing equipment. The demand for plastics has been historically on the rise since they were first discovered. The global plastics market is characterized by a high degree of fragmentation, with numerous small players that offer unique commercial and skill sets. Relatively low entry barriers in the industry constantly encourage the establishment of new players. The phenomenal increase in the demand for plastics from such burgeoning fields as wind energy, developmental infrastructure, and automobile industries has lead to more and more entries into this already fragmented market. Industry data has shown that the U.S. plastics market alone, the fourth-largest manufacturing sector in the country, provides more than 1.5 million jobs and contributes $320 billion or more in annual shipments.

In the mid 1990s, a need to organize and consolidate the global plastic market was felt, when the developing world became a major market. The plastics industry in various developing nation began to offer competition to companies that were globally consolidated. Technological advancements allowed them to compete with the existing players in terms of product quality, cost and quantity. In addition, joint ventures with existing market stalwarts, foreign investments from the developed nations, and easier access to technology from the developed world, have all been factors in the opening up of new possibilities in the global growth of this industry. Phenomenal technological developments in the plastic machinery sector have coupled with in-pace developments in petrochemicals, to facilitate the building up of capacities of plastic processors to service domestic as well as overseas markets.

Some segments in the industry have done better than others. The composite plastics segment for example, including Wood Plastics Composites, is a fast growing part of the global market. The extraordinary recent growth in the sales of products made from a mixture of wood flour and plastics in North America has been ongoing for a decade and more now. These materials contain 40 to 80% wood, but their outdoor durability is like that of plastics leading to much lower maintenance costs. Expensive wood working operations are unnecessary and the materials can be extruded, co-extruded and veneered. In Europe, a considerable variety of WPC products are becoming available now and the European production is set to rise from 99,288 tons in 2005 to nearly 145,000 tons this year.

The biggest user of WPC in Europe is the auto industry, with about half the total consumption, while it accounts for a mere 7% of worldwide WPC consumption. There is enormous scope for growth in WPC sales in the construction and furniture sectors. The number of companies developing furniture components made of WPC has grown phenomenally, the world over. Sales are also expected to shoot up in infrastructure applications such as highway sound barriers and waterfront fixtures, which are currently mostly made of wood. Decking has been one of the biggest growth sectors for WPC in the USA and a number of European countries too are showing interest in decking. Other possible high growth areas are siding or cladding, fencing and interior construction items.
Definitions

Additives: A group of specialty chemicals incorporated into plastics before or during processing, or to the surfaces of finished products to modify the behavior of plastics during processing or to impart useful properties to fabricated plastic articles.

Extrusion: One of the most common plastics processing techniques in which resins are melted, heated and pumped for processing, using extrusion machines with one or more internal screws.

Coextrusion: A process where parts are blow-molded with walls containing two or more layers of different material, offering a wide latitude for material selection and the use of recycled materials.

Compounding: The incorporation of additional ingredients for processing in order to have optimal properties, including adding additives to improve the polymer's physical properties, stability or processability.

Trends and Predictions:

Many improvements in the strength and functionalities of plastics can be expected over the next two or three years to help market penetration in a number of areas, all over the world. New and better technical standards are being developed, and basic product research continues on most plastics to improve their adaptability to key manufacturing processes that are efficient and economical.

The plastics industry has been under intense scrutiny in recent years due to a number of concerns with respect to health and environmental safety issues. The industry has responded proactively to these pressures by reviewing internal practices and undertaking new research into ways of reducing the risks. Sustainability issues are being addressed and many recycling projects have been set up.