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Plastic is the generic name for a family of synthetic materials derived from petrochemicals. It is often product of two or more components.
There are many families of plastics and polymers being used in construction industry, such as acrylics, composites, expanded polystyrene, polycarbonates, polyethylene, polypropylene, and polyvinyl chloride.
Plastics are very versatile construction materials. The unique properties of plastics allow them to form tight seals, and they are useful as both thermal and electrical insulators. Plastics are strong yet lightweight, so they are easy to transport & maneuver. They are also durable and resistant to bumps and scratches. They do not rot or corrode (like wood or metal), and have excellent weatherability. Plastics can be shaped for use by extrusion, bending, molding, and cutting, allowing a wide variety of shapes to be made of plastic. Plastics can also be made any color through the addition of pigments.
Nevertheless, there are limitations to the use of plastic. Plastics have a low modulus of elasticity, which makes them unsuitable for load-bearing applications. Plastics can also degrade when exposed to sunlight, and many types of plastic soften and deform when heated. Plastics are also flammable and often release toxic fumes when burnt. They are not biodegradable and difficult to recycle, so they are not an environmentally friendly building material. [1]
Below are some uses for plastics in the construction industry:
Biopolymers are natural polymers produced by the cells of living organisms. Like other polymers, biopolymers consist of monomeric units that are covalently bonded in chains to form larger molecules. There are three main classes of biopolymers, classified according to the monomers used and the structure of the biopolymer formed: polynucleotides, polypeptides, and polysaccharides. The Polynucleotides, RNA and DNA, are long polymers of nucleotides. Polypeptides include proteins and shorter polymers of amino acids; some major examples include collagen, actin, and fibrin. Polysaccharides are linear or branched chains of sugar carbohydrates; examples include starch, cellulose, and alginate. Other examples of biopolymers include natural rubbers, suberin and lignin, cutin and cutan, melanin, and polyhydroxyalkanoates (PHAs).
Biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi. It is generally assumed to be a natural process, which differentiates it from composting. Composting is a human-driven process in which biodegradation occurs under a specific set of circumstances.
Polymer degradation is the reduction in the physical properties of a polymer, such as strength, caused by changes in its chemical composition. Polymers and particularly plastics are subject to degradation at all stages of their product life cycle, including during their initial processing, use, disposal into the environment and recycling. The rate of this degradation varies significantly; biodegradation can take decades, whereas some industrial processes can completely decompose a polymer in hours.
A drinking straw is a utensil that is intended to carry the contents of a beverage to one's mouth. Disposable straws are commonly made from plastics. However, environmental concerns related to plastic pollution and new regulation have led to rise in reusable and biodegradable straws. Following a rise in regulation and public concern, some companies have even voluntarily banned or reduced the number of plastic straws used. Alternative straws are often made of reusable materials like silicone or metal or alternative disposable and biodegradable materials like paper, cardboard, pasta, or bamboo.
Plastic shopping bags, carrier bags, or plastic grocery bags are a type of plastic bag used as shopping bags and made from various kinds of plastic. In use by consumers worldwide since the 1960s, these bags are sometimes called single-use bags, referring to carrying items from a store to a home. However, it is rare for bags to be worn out after single use and in the past some retailers incentivised customers to reuse 'single use' bags by offering loyalty points to those doing so. Even after they are no longer used for shopping, reuse of these bags for storage or trash is common, and modern plastic shopping bags are increasingly recyclable or compostable - at the Co-op for example. In recent decades, numerous countries have introduced legislation restricting the provision of plastic bags, in a bid to reduce littering and plastic pollution.
A plastic bag, poly bag, or pouch is a type of container made of thin, flexible, plastic film, nonwoven fabric, or plastic textile. Plastic bags are used for containing and transporting goods such as foods, produce, powders, ice, magazines, chemicals, and waste. It is a common form of packaging.
A bin bag, rubbish bag, garbage bag, bin liner, trash bag or refuse sack is a disposable receptable for solid waste. These bags are useful to line the insides of waste containers to prevent the insides of the container from becoming coated in waste material. Most bags today are made out of plastic, and are typically black, white, or green in color.
Plastic recycling is the processing of plastic waste into other products. Recycling can reduce dependence on landfill, conserve resources and protect the environment from plastic pollution and greenhouse gas emissions. Recycling rates lag behind those of other recoverable materials, such as aluminium, glass and paper. From the start of plastic production through to 2015, the world produced around 6.3 billion tonnes of plastic waste, only 9% of which has been recycled and only ~1% has been recycled more than once. Of the remaining waste, 12% was incinerated and 79% was either sent to landfills or lost to the environment as pollution.
A water bottle is a container that is used to hold liquids, mainly water, for the purpose of transporting a drink while travelling or while otherwise away from a supply of potable water.
Bioplastics are plastic materials produced from renewable biomass sources. Historically, bioplastics made from natural materials like shellac or cellulose had been the first plastics. Since the end of the 19th century they have been increasingly superseded by fossil-fuel plastics derived from petroleum or natural gas. Today, in the context of bioeconomy and circular economy, bioplastics are gaining interest again. Conventional petro-based polymers are increasingly blended with bioplastics to manufacture "bio-attributed" or "mass-balanced" plastic products - so the difference between bio- and other plastics might be difficult to define.
Polyethylene or polythene film biodegrades naturally, albeit over a long period of time. Methods are available to make it more degradable under certain conditions of sunlight, moisture, oxygen, and composting and enhancement of biodegradation by reducing the hydrophobic polymer and increasing hydrophilic properties.
Biodegradable plastics are plastics that can be decomposed by the action of living organisms, usually microbes, into water, carbon dioxide, and biomass. Biodegradable plastics are commonly produced with renewable raw materials, micro-organisms, petrochemicals, or combinations of all three.
Polymer engineering is generally an engineering field that designs, analyses, and modifies polymer materials. Polymer engineering covers aspects of the petrochemical industry, polymerization, structure and characterization of polymers, properties of polymers, compounding and processing of polymers and description of major polymers, structure property relations and applications.
Sustainable packaging is packaging materials and methods that result in improved sustainability. This involves increased use of life cycle inventory (LCI) and life cycle assessment (LCA) to help guide the use of packaging which reduces the environmental impact and ecological footprint. It includes a look at the whole of the supply chain: from basic function, to marketing, and then through to end of life (LCA) and rebirth. Additionally, an eco-cost to value ratio can be useful The goals are to improve the long term viability and quality of life for humans and the longevity of natural ecosystems. Sustainable packaging must meet the functional and economic needs of the present without compromising the ability of future generations to meet their own needs. Sustainability is not necessarily an end state but is a continuing process of improvement.
Twin-wall plastic, specifically twin-wall polycarbonate, is an extruded multi-wall polymer product created for applications where its strength, thermally insulative properties, and moderate cost are ideal. Polycarbonate, which is most commonly formed through the reaction of Bisphenol A and Carbonyl Chloride, is an extremely versatile material. It is significantly lighter than glass, while managing to be stronger, more flexible, and more impact resistant. Twin-wall polycarbonate is used most commonly for green houses, where it can support itself in a structurally sound configuration, limit the amount of UV light due to its nominal translucence, and can withstand the rigors of daily abuse in an outdoor environment. The stagnant air in the cellular space between sheets provides insulation, and additional cell layers can be extruded to enhance insulative properties at the cost of light transmission.
Biodegradable bags are bags that are capable of being decomposed by bacteria or other living organisms.
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be molded, extruded or pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive to produce, has led to their widespread use. Plastics typically are made through human industrial systems. Most modern plastics are derived from fossil fuel-based chemicals like natural gas or petroleum; however, recent industrial methods use variants made from renewable materials, such as corn or cotton derivatives.
Plastic pollution is the accumulation of plastic objects and particles in the Earth's environment that adversely affects humans, wildlife and their habitat. Plastics that act as pollutants are categorized by size into micro-, meso-, or macro debris. Plastics are inexpensive and durable, making them very adaptable for different uses; as a result, manufacturers choose to use plastic over other materials. However, the chemical structure of most plastics renders them resistant to many natural processes of degradation and as a result they are slow to degrade. Together, these two factors allow large volumes of plastic to enter the environment as mismanaged waste which persists in the ecosystem and travels throughout food webs.
Biodegradable additives are additives that enhance the biodegradation of polymers by allowing microorganisms to utilize the carbon within the polymer chain as a source of energy. Biodegradable additives attract microorganisms to the polymer through quorum sensing after biofilm creation on the plastic product. Additives are generally in masterbatch formation that use carrier resins such as polyethylene (PE), polypropylene (PP), polystyrene (PS) or polyethylene terephthalate (PET).
Conservation and restoration of objects made from plastics is work dedicated to the conservation of objects of historical and personal value made from plastics. When applied to cultural heritage, this activity is generally undertaken by a conservator-restorer.