Polymers are of two types: naturally occurring and synthetic or man made.
Commercial Uses of Polymers
| Polymer | Monomer | Uses of Polymer |
|---|
| Rubber | Isoprene (1, 2-methyl 1 – 1, 3-butadiene) | Making tyres, elastic materials |
| BUNA – S | (a) 1, 3-butadiene (b) Styrene | Synthetic rubber |
| BUNA – N | (a) 1, 3-butadiene (b) Vinyl Cyanide | Synthetic rubber |
| Teflon | Tetra Flouro Ethane | Non-stick cookware – plastics |
A1.1 PHYSICAL PROPERTIESPhysical properties of polymers include molecular weight, molar volume, density, degree of polymerization, crystallinity of material, and so on.
Examples of synthetic polymers include nylon, polyethylene, polyester, Teflon, and epoxy. Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose and proteins.
Some of the useful properties of various engineering polymers are high strength or modulus to weight ratios (light weight but comparatively stiff and strong), toughness, resilience, resistance to corrosion, lack of conductivity (heat and electrical), color, transparency, processing, and low cost.
A polymer is a very big molecule formed by the combination of a large number of small molecules. The small molecules which join together to form a polymer is called monomer. The monomer which make a polymer may be of the same compound or of different compounds.
Answer: Most glass is made from sand, and when we melt down the sand, we usually add some sodium carbonate. These linear, and yes, inorganic materials have a structure very similar to glass, and they're considered polymers.
By definition, polymers are large molecules made by bonding (chemically linking) a series of building blocks. The word polymer comes from the Greek words for “many parts.†Each of those parts is scientists call a monomer (which in Greek means “one partâ€). Think of a polymer as a chain, with each of its links a monomer.
As mentioned above, polymers that are classified as plastics can be divided into two major categories: thermoplastics and thermosets. Thermoplastics such as polyethylene and polystyrene are capable of being molded and remolded repeatedly.
From the utility point of view they can be classified into three main categories: thermoplastics, elastomers and synthetic fibers. They are commonly found in a variety of products worldwide. A wide variety of synthetic polymers are available with variations in main chain as well as side chains.
Polymers are more resistant to chemicals than their metal counterparts. Polymer parts do not require post-treatment finishing efforts, unlike metal. Polymer and composite materials are up to ten times lighter than typical metals. Polymers are naturally radar absorbent as well as thermally and electrically insulating.
Polymers are used in almost every area of modern living. Grocery bags, soda and water bottles, textile fibers, phones, computers, food packaging, auto parts, and toys all contain polymers. Even more-sophisticated technology uses polymers.
Addition Polymers
| Chemical Name | Trade Name or Common Name |
|---|
| polyethylene | |
| poly(tetrafluoroethylene) | Teflon |
| polypropylene | Herculon |
| polyisobutylene | butyl rubber |
The Basics On 7 Common Types of Plastic
- 1) Polyethylene Terephthalate (PET or PETE)
- 2) High-Density Polyethylene (HDPE)
- 3) Polyvinyl Chloride (PVC or Vinyl)
- 4) Low-Density Polyethylene (LDPE)
- 5) Polypropylene (PP)
- 6) Polystyrene (PS or Styrofoam)
- 7) Other.
1.3 Linear, Branched, and Cross-linked Polymers
Polyethylene, PVC, Nylon 66, and polymethyl methacrylate are some linear commercial examples found in this book. Branched polymers can be visualized as a linear polymer with side chains of the same polymer attached to the main chain.And even our DNA is a polymer—it's made of monomers called nucleotides. The first man-made polymers were actually modified versions of these natural polymers.
Polymers can exist organically or be created synthetically, and consist of chains of joined individual molecules or monomers. Plastics are a type of polymer composed of chains of polymers which can be partially organic or fully synthetic. Simply put, all plastics are polymers, but not all polymers are plastics.
Polymers are formed by two main ways called addition and condensation polymerization. In addition, polymerization, an initiator (or catalyst) reacts with a starting monomer. The unsatisfied bond is free to react with another monomer, thus adding to the chain.
Proteins are polymers in which the 20 natural amino acids are linked by amide bonds. However, in general, the amino acid sequence and the structure being formed depend on the type of structural protein, and it is difficult to identify a structural protein based on the sequence or structure alone.
Source-Based Nomenclature
- Homopolymers.
- Copolymers.
- Non-linear polymers.
- Regular single-strand organic polymers.
- Regular double-strand organic polymers.
Natural rubber is a polymer, a long, chain like molecule that contains repeating subunits. The term polymer comes from the Greek “poly” meaning many and “mer” meaning parts. The chemical name for natural rubber is polyisoprene. The monomer (meaning “one-part”) from which it is built is isoprene.
