Semi synthetic polymers pdf file

They have wide range of applications so selection of. Semi synthetic polymers cellulose derivatives as cellulose acetate rayon and cellulose nitrate, etc. Functional synthetic and semisynthetic polymers in biomedical. Synthetic polymers are those which are humanmade polymers. Although many polymers were made in the following years, the technology to mass produce them was not developed until world war ii, when there was a need to develop synthetic rubber for tires and other wartime applications and nylon for parachutes. One of the most common and versatile polymers is polyethylene. Rubbers elastomers are then discussed, follo w ed by condensation pol ymers and ther mosetting pol ymers. Fibres fibres belong to a class of polymers which are threadlike and can be woven into fabrics. The polymers obtained by simple chemical treatment of natural polymers to change their physical properties like starch, silicones 3. Polymers polymers are the giant molecules of chemistry. Biodegradable synthetic and semisynthetic polymers wiley online.

Pdf biodegradable polymers offer great potential in nanotechnology, including drug delivery systems and medical devices. Application of natural and semisynthetic polymers for the delivery of. Thousands of new, highquality pictures added every day. These are widely used for making clothes, nets, ropes, gauzes, etc. Find synthetic polymers stock images in hd and millions of other royaltyfree stock photos, illustrations and vectors in the shutterstock collection. Natural, synthetic and semisynthetic polymers book chapter. The degradation rate of this polymer is relatively slow, similar to that of alginates. They are derived from naturally occurring polymers and undergo further chemical modification. Polyethylene is considered to be as one of the simplest polymer, it has ethene or ethylene as the monomer unit whereas the linear polymer is known as the high density polyethylenehdpe. The cellulose backbone is a naturally occurring polymer, and then it is acetylated in a synthetic reaction to convert the. They are broadly classified as natural polymers and synthetic polymers. Synthetic polymers types and examples polymer uses. In addition to these two major groups, there are other types of materials in which the original polymer is a natural product but are chemically andor physically. Rayon and other cellulose derivatives like cellulose nitrate, cellulose acetate etc.

The chapter concludes with a brief examination of the chem ical proper ties of pol ymers. Polymers can be considered to be for med from the bond ing of a large number of indi vidual units, called mono mers. Pdf natural and semisynthetic polymers in pharmaceutical. The small buildingblock molecules are called monomers. Examples are proteins, cellulose, starch, resins and rubber.

Synthetic polymers a variety of synthetic polymers as plastic polythene, synthetic fibres nylon 6,6 and synthetic rubbers buna s are examples of man. Fibres possess high tensile strength because the chains possess strong intermolecular forces such as hydrogen bonding. Synthetic polymers are a mainstay of modern life, but nature also makes polymers. Viscose rayon in the form of a thin transparent film is known as cellophane. These polymers are found in nature, example plants and animals. Additionally, semisynthetic polymers based on natural polymers grafted. Plastic is the most common and widely used synthetic polymer.

They are quite cheap to make and easy to form into shapes. Total reflectance ftir spectroscopy, semisynthetic polymers, plastics, non invasive. A polymer is analogous to a necklace made from many small beads monomers. A chemical reaction forming polymers from monomers is called polymerization, of which there are many types. Synthetic, semisynthetic or natural polymers or inorganic materials are frequently used for the development of drug delivery systems. A survey is reported on our activity performed in the last few years on the preparation of new synthetic and semisynthetic polymeric materials endowed with. Agarose exhibits a temperaturesensitive solubility in water and has found. A common name for many synthetic polymer materials is plastic, which comes from the greek word plastikos, suitable for molding or shaping. It is used in industries and various dairy products.