CHARACTERISTICS OF POLYMERS

 

Chemical characteristics

  • Polymers often have the reactivity of the molecules that make up the monomers at the ends of the chains. Synthetic polymers are not very reactive, although the presence of acids and organic solvents tend to corrode them quickly.

 Physical characteristics

  • They tend to be poor conductors of electricity, which is why they are often used as insulators. It is also frequent that they present electrochromism (change of color before electricity) and in some cases phosphorescence or fluorescence.

  • Polymers are usually crystalline in cases of more ordered structures, although their presentation can be very varied. At low temperatures they can acquire more hardness and vitreous properties, while at high temperatures they are more elastic until they reach their melting temperature (Tf) at which their cells melt Much higher is the decomposition temperature, at which the bonds between monomers are broken.

  • In general terms, the most interesting thing about polymers is their mechanical properties: viscoelasticity, elasticity, plastic flow and fracture, which makes them ideal materials for numerous industrial activities.

Comentarios

Publicar un comentario

Entradas populares de este blog

POLYMERIZATION

Imagen
 The process of building polymers is polymerization and consists of the union by covalent bonds of the different monomers that comprise it. This process can be of two types: By condensation.  It results in copolymers and homopolymers, through the loss of a small molecule (of water, for example) at each monomer bond. It is also known as step polymerization. By addition.  It occurs in a three-phase process: initiation, propagation, and termination, during which homolytic cleavage occurs and monomers come together. No low molecular mass molecules are released.
Leer más

EXAMPLES OF POLYMERS

Imagen
   Polymers are very important compounds, since some fulfill vital functions in living beings. For example: proteins, DNA. Many of them are present in nature and in practically everything that surrounds us. For example: plastic in a toy; the rubber in car tires; the wool in a sweater. Some well known are: Cellulose . It is the biopolymer from which wood and paper are made. DNA . It is the deoxyribonucleic acid present in the nucleus of our cells is a good example of a natural polymer. The PCV . Polyvinyl chloride is obtained by polymerizing vinyl chloride and is one of the most versatile plastic derivatives that exist. Starch . It is a white, odorless and tasteless substance, composed of two types of sugars. It is used by plants as an energy reserve material. Nylon . Known as nylon or nylon, it is a polyamide used in the manufacture of traditional female stockings as well as for ropes, parachutes and thousands of other textile supplies. Bakelite . It is the first synthetic plastic subs
Leer más

POLYMER'S APPLICATIONS AND DEFECTS

Imagen
Polymers are enormously versatile. Their resistance to electrical conduction has made them ideal for coatings and insulation. Some, with a very high melting point, are also used to thermally insulate kitchen utensils. In other cases, they are suitable construction materials for coatings and waterproofing, or as a structural material. Many petroleum-derived polymers are the raw material for making plastics of all kinds and functions, from containers, tools, parts, toys, etc. Idustrial polymers often have defects, which have to do with non-homoeneous distribution of their monomers, or the contamination of the chain with elements foreign to the substance. These defects are usually not visible to the naked eye and require examination by LUMOS microscopes
Leer más