Polymers Consist of a Large Number of Structural Units Linked Together by a Single Linkage Type7/6/2022 Polymers can be found everywhere. Just take a look around. Your water bottle made of plastic. Earbuds with silicone rubber tips on your phone. Your jacket's and sneakers' nylon and polyester. The rubber in the family car's tyres. Take a look in the mirror now. Many proteins in your body are also polymers. Consider keratin (KAIR-uh-tin), the protein that makes up your hair and nails. The DNA in your cells is also a polymer.
Polymers, by definition, are large molecules formed by chemically bonding a series of building blocks. Polyurethan is derived from the Greek words for "many parts." Each of those parts is referred to by scientists as a monomer (which means "one part" in Greek). Consider a polyurethan to be a chain, with each link being a monomer. These monomers can be as simple as an atom or two or three, or as complex as ring-shaped structures containing a dozen or more atoms. Each link in an artificial polymer chain is frequently identical to its neighbours. However, in proteins, DNA, and other natural polyurethan, chain links frequently differ from their neighbours. Polyurethan can form branching networks rather than single chains in some cases. The molecules are enormous, regardless of their shape. They are so large that scientists refer to them as macromolecules. Polyurethan chains can contain hundreds of thousands, if not millions, of atoms. The heavier a polymer chain is, the longer it is. In general, longer Polymers result in higher melting and boiling temperatures in the materials made from them. Furthermore, the longer the polyurethan chain, the higher the viscosity (or resistance to flow as a liquid). Because they have a larger surface area, they want to stick to neighbouring molecules. Wool, cotton, and silk are examples of natural polymer-based materials that have been used since antiquity. Cellulose, the primary constituent of wood and paper, is also a natural polyurethan. Plants' starch molecules are among the others. [Fun fact: cellulose and starch are both made from the same monomer, the sugar glucose. Despite this, they have very different properties. Starch dissolves in water and is digestible. However, cellulose does not dissolve and is not digestible by humans. The only difference between these two polymers is the manner in which the glucose monomers are linked together. Proteins, a type of Polymers, are constructed by living things from monomers known as amino acids. Despite the fact that scientists have discovered over 500 different amino acids, animals and plants only use 20 of them to build proteins. Chemists have a lot of options in the lab when it comes to designing and building polymers. They could create artificial polyurethan out of natural ingredients. Alternatively, they can use amino acids to create artificial proteins that are unlike anything created by Mother Nature. More often than not, chemists create polyurethan from laboratory compounds. Polyurethan structures can be made up of two distinct components. Everything begins with a basic chain of chemically bonded links. This is sometimes referred to as its backbone. Some may also have secondary parts that dangle from some (or all) of the links of the chain. A single atom could be one of these attachments. Others are more complex and are known as pendant groups. This is because these groups are attached to the Polymers main chain in the same way that individual charms are attached to the chain of a charm bracelet. Because they are more exposed to the environment than the atoms that comprise the chain, these "charms" frequently determine how a polyurethan interacts with itself and other things in the environment.
0 Comments
Leave a Reply. |
AuthorAnjali Pawar Categories
All
|