Some familiar household synthetic polymers include: Nylons in textiles and fabrics, Teflon in non-stick pans, Bakelite for electrical switches, polyvinyl chloride (PVC) in pipes, etc. The common PET bottles are made of a synthetic polymer, polyethylene terephthalate. The plastic kits and covers are mostly made of synthetic polymers like polythene, and tires are manufactured from polybutadienes. [1] However, due to the environmental issues created by these synthetic polymers which are mostly non-biodegradable and often synthesized from petroleum, alternatives like bioplastics are also being considered. They are however expensive when compared to the synthetic polymers. [2]
Artificial polymer: Man-made polymer that is not a biopolymer.
Note 1: Artificial polymer should also be used in the case of chemically
modified biopolymers.Note 2: Biochemists are now capable of synthesizing copies of biopolymers
that should be named Synthetic biopolymer to make a distinction
with true biopolymers.Note 3: Genetic engineering is now capable of generating non-natural analogues
of biopolymers that should be referred to as artificial biopolymers, e.g.,
artificial protein, artificial polynucleotide, etc. [3]
The eight most common types of synthetic organic polymers, which are commonly found in households are:
Polymer | Abbreviation | Properties | Uses | |
---|---|---|---|---|
Low-density polyethylene | LDPE | Chemically inert, flexible, insulator | Squeeze bottles, toys, flexible pipes, insulation cover (electric wires), six-pack rings, etc. | |
High-density polyethylene | HDPE | Inert, thermally stable, tough and high tensile strength | Bottles, pipes, inner insulation (dielectric) of coax cable (see also PTFE), plastic bags, etc. | |
Polypropylene | PP | Resistant to acids and alkalies, High tensile strength | Auto parts, industrial fibers, food containers, liner in bags, dishware and as a wrapping material for textiles and food | |
Polystyrene (thermocole) | PS | Thermal insulator. Properties depends on the form, expanded form is tough and rigid | Petri dishes, CD case, plastic cutlery | |
Polytetrafluoroethylene | PTFE | Very low coefficient of friction, excellent dielectric properties, chemically inert | Low friction bearings, non-stick pans, inner insulation (dielectric) of coax cable (see also HDPE), coating against chemical attack etc. | |
Polyvinyl chloride | PVC | Insulator, flame retardant, chemically inert | Pipe (mainly draining), fencing, lawn chairs, hand-bags, curtain clothes, non-food bottles, raincoats, toys, vinyl flooring, electrical installation insulations, etc. | |
Polychlorotrifluoroethylene | PCTFE | Stable to heat and thermal attacks, high tensile strength and non wetting | valves, seals, gaskets etc. |
These polymers are often better known through their brand names, for instance:
Brand Name | Polymer | Characteristic properties | Uses |
---|---|---|---|
Bakelite | Phenol-formaldehyde resin | High electric, heat and chemical resistance | Insulation of wires, manufacturing sockets, electrical devices, brake pads, etc. |
Kevlar | Para-aramid fibre | High tensile strength | Manufacturing armour, sports and musical equipment. Used in the field of cryogenics |
Twaron | Para-aramid | Heat resistant and strong fibre | Bullet-proof body armor, helmets, brake pads, ropes, cables and optical fibre cables, etc. and as an asbestos substitute |
Mylar | Polyethylene terephthalate film | High strength and stiffness, less permeable to gases, almost reflects light completely | Food packaging, transparent covering over paper, reflector for rollsigns and solar cooking stoves |
Neoprene | Polychloroprene | Chemically inert | Manufacturing gaskets, corrosion resistant coatings, waterproof seat covers, substitute for corks and latex |
Nylon | Polyamide | Silky, thermoplastic and resistant to biological and chemical agents | Stockings, fabrics, toothbrushes. Molded nylon is used in making machine screws, gears etc. |
Nomex | Meta-aramid polymer | Excellent thermal, chemical, and radiation resistance, rigid, durable and fireproof . | Hood of firefighter's mask, electrical lamination of circuit boards and transformer cores and in Thermal Micrometeoroid Garment |
Orlon | Polyacrylonitrile (PAN) | Wool-like, resistant to chemicals, oils, moths and sunlight | Used for making clothes and fabrics like sweaters, hats, yarns, rugs, etc., and as a precursor of carbon fibres |
Rilsan | Polyamide 11 & 12 | Bioplastic | Used in high-performance applications such as sports shoes, electronic device components, automotive fuel lines, pneumatic airbrake tubing, oil and gas flexible pipes and control fluid umbilicals, and catheters. |
Technora | Copolyamid | High tensile strength, resistance to corrosion, heat, chemicals and saltwater | Used for manufacturing optical fiber cables, umbilical cables, drumheads, automotive industry, ropes, wire ropes and cables |
Teflon | Polytetrafluoroethylene (PTFE) | Very low coefficient of friction, excellent dielectric properties, high melting, chemically inert | Plain bearings, gears, non-stick pans, etc. due to its low friction. Used as a tubing for highly corrosive chemicals. |
Ultem | Polyimide | Heat,flame and solvent resistant. Has high dielectric strength | Used in medical and chemical instrumentation, also in guitar picks |
Vectran | aromatic polyester | High thermal and chemical stability. Golden color. Has high strength, low creep, and is moisture resistant | Used as reinforcing fibres for ropes, cables, sailcloth. Also used in manufacturing badminton strings, bike tires and in electronics applications. Is the key component of a line of inflatable spacecraft developed by Bigelow Aerospace |
Viton | Polytetrafluoroethylene (PTFE) | Elastomer | Depends on the grade of the polymer. Viton B is used in chemical process plants and gaskets. |
Zylon | poly-p-phenylene-2,6-benzobisoxazole (PBO) | Very high tensile strength and thermal stability | Used in tennis racquets, table tennis blades, body armor, etc. |
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).
A monomer is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization.
A polymer is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals.
Polyvinyl chloride (alternatively: poly(vinyl chloride), colloquial: vinyl or polyvinyl; abbreviated: PVC) is the world's third-most widely produced synthetic polymer of plastic (after polyethylene and polypropylene). About 40 million tons of PVC are produced each year.
Petrochemicals are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable sources such as maize, palm fruit or sugar cane.
Fiber or fibre is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, for example carbon fiber and ultra-high-molecular-weight polyethylene.
A thermoplastic, or thermosoftening plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling.
In polymer chemistry, an addition polymer is a polymer that forms by simple linking of monomers without the co-generation of other products. Addition polymerization differs from condensation polymerization, which does co-generate a product, usually water. Addition polymers can be formed by chain polymerization, when the polymer is formed by the sequential addition of monomer units to an active site in a chain reaction, or by polyaddition, when the polymer is formed by addition reactions between species of all degrees of polymerization. Addition polymers are formed by the addition of some simple monomer units repeatedly. Generally polymers are unsaturated compounds like alkenes, alkalines etc. The addition polymerization mainly takes place in free radical mechanism. The free radical mechanism of addition polymerization completed by three steps i.e. Initiation of free radical, Chain propagation, Termination of chain.
Polymer chemistry is a sub-discipline of chemistry that focuses on the structures of chemicals, chemical synthesis, and chemical and physical properties of polymers and macromolecules. The principles and methods used within polymer chemistry are also applicable through a wide range of other chemistry sub-disciplines like organic chemistry, analytical chemistry, and physical chemistry. Many materials have polymeric structures, from fully inorganic metals and ceramics to DNA and other biological molecules. However, polymer chemistry is typically related to synthetic and organic compositions. Synthetic polymers are ubiquitous in commercial materials and products in everyday use, such as plastics, and rubbers, and are major components of composite materials. Polymer chemistry can also be included in the broader fields of polymer science or even nanotechnology, both of which can be described as encompassing polymer physics and polymer engineering.
Polyvinyl fluoride (PVF) or –(CH2CHF)n– is a polymer material mainly used in the flammability-lowering coatings of airplane interiors and photovoltaic module backsheets. It is also used in raincoats and metal sheeting. Polyvinyl fluoride is a thermoplastic fluoropolymer with a repeating vinyl fluoride unit, and it is structurally very similar to polyvinyl chloride.
Wood–plastic composites (WPCs) are composite materials made of wood fiber/wood flour and thermoplastic(s) such as polythene (PE), polypropylene (PP), polyvinyl chloride (PVC), or polylactic acid (PLA).
Chain-growth polymerization (AE) or chain-growth polymerisation (BE) is a polymerization technique where unsaturated monomer molecules add onto the active site on a growing polymer chain one at a time. There are a limited number of these active sites at any moment during the polymerization which gives this method its key characteristics.
In polymer chemistry, vinyl polymers are a group of polymers derived from substituted vinyl monomers. Their backbone is an extended alkane chain [−CH2−CHR−]. In popular usage, "vinyl" refers only to polyvinyl chloride (PVC).
Bioplastics are plastic materials produced from renewable biomass sources, such as vegetable fats and oils, corn starch, straw, woodchips, sawdust, recycled food waste, etc. Some bioplastics are obtained by processing directly from natural biopolymers including polysaccharides and proteins, while others are chemically synthesised from sugar derivatives and lipids from either plants or animals, or biologically generated by fermentation of sugars or lipids. In contrast, common plastics, such as fossil-fuel plastics are derived from petroleum or natural gas.
A plastic bottle is a bottle constructed from high-density or low density plastic. Plastic bottles are typically used to store liquids such as water, soft drinks, motor oil, cooking oil, medicine, shampoo, milk, and ink. The size ranges from very small bottles to large carboys. Consumer blow molded containers often have integral handles or are shaped to facilitate grasping.
Plastic pipe is a tubular section, or hollow cylinder, made of plastic. It is usually, but not necessarily, of circular cross-section, used mainly to convey substances which can flow—liquids and gases (fluids), slurries, powders and masses of small solids. It can also be used for structural applications; hollow pipes are far stiffer per unit weight than solid members.
Plastic film is a thin continuous polymeric material. Thicker plastic material is often called a "sheet". These thin plastic membranes are used to separate areas or volumes, to hold items, to act as barriers, or as printable surfaces.
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 moulded, 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 its 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.
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate), commonly known as PHBV, is a polyhydroxyalkanoate-type polymer. It is biodegradable, nontoxic, biocompatible plastic produced naturally by bacteria and a good alternative for many non-biodegradable synthetic polymers. It is a thermoplastic linear aliphatic polyester. It is obtained by the copolymerization of 3-hydroxybutanoic acid and 3-hydroxypentanoic acid. PHBV is used in speciality packaging, orthopedic devices and in controlled release of drugs. PHBV undergoes bacterial degradation in the environment.