Skip to main content

Kevlar.

Kevlar.

  • Kevlar is a man made fibre.
  • Kevlar is a polyamide formed from benzene-1,4-diamine and benzene-1,4-dicarboxylic acid.
    This image shows synthesis of Kevlar from benzene-1,4-diamine and benzene-1,4-dicarboxylic acid.
    Kevlar.
  • Kevlar can also be produced from benzene-1,4-diamine and benzene-1,4-dicarbonyl dichloride.
    This image shows synthesis of Kevlar from benzene-1,4-diamine and benzene-1,4-dicarbonyl dichloride.
    Kevlar.
  • It is strong but relatively light.
  • Kevlar can resist attacks from many different chemicals, though long exposure to strong acids or bases will degrade it over time.
  • Unlike most plastics it does not melt. It is reasonably good at withstanding temperatures and decomposes only at ~450°C.
  • Kevlar is used in making military body armour and jackets.
  • Military helmets are made from Kevlar.
  • Its resistance to chemicals and temperature extremes make it an ideal component for ropes and cables.
  • Kevlar is used as a strength member in optical fibre cables.
  • Protection vest are made with Kevlar.
    This image shows uses of Kevlar in military body armour, military helmets,ropes, cables, optical fibre cables, protection vests.
    Uses of Kevlar.

Questions on Kevlar;

Q1) What is Kevlar?
Ans) Kevlar is a man made fibre.
Q2) How is Kevlar prepared?
Ans) Kevlar is a polyamide formed from benzene-1,4-diamine and benzene-1,4-dicarboxylic acid.
Kevlar can also be produced from benzene-1,4-diamine and benzene-1,4-dicarbonyl dichloride.
Q3) Write some properties of Kevlar?
Ans) Some properties of Kevlar are given below;
1) It is strong but relatively light.
2) Kevlar can resist attacks from many different chemicals, though long exposure to strong acids or bases will degrade it over time.
3) Unlike most plastics it does not melt. It is reasonably good at withstanding temperatures and decomposes only at ~450°C.
Q4) Write some uses of Kevlar?
Ans) Some uses of Kevlar are given below;
1) Kevlar is used in making military body armour and jackets.
2) Military helmets are made from Kevlar.
3) Its resistance to chemicals and temperature extremes make it an ideal component for ropes and cables.
4) Kevlar is used as a strength member of optical fibre cables.
5) Protection vest are made with Kevlar. Next

Comments

Post a Comment

Popular posts from this blog

Determination of molecular weight of polymers by viscosity method.

Determination of molecular weight of polymers by viscosity method. It is a simple method for determining the molecular weight of polymers. Addition of polymers in the solvent increases the viscosity of the solvent, due to introduction of inhomogeneities by the polymers. If η₀ is the viscosity of the solvent and η is the viscosity of the solution at the same temperature, then the relative viscosity is given by Relative viscosity. Specific viscosity:  It is defined as the relative increase in viscosity and is given as Specific viscosity. Reduced viscosity: It is defined as the relative increase in viscosity per unit concentration (C) of polymer and is given as Reduced viscosity. Intrinsic viscosity: The reduced viscosity is dependent on concentration (C). If a graph is plotted between  reduced viscosity vs concentration then the extraplotation value when C=0 is called intrinsic viscosity. Intrinsic viscosity. Graph of reduced viscosity vs concentr
2 comments
Read more

Polypropylene (PP)

Polypropylene (PP). Polypropylene (PP) is also known as polypropene. Polypropylene is made from the polymerisation of propylene gas in the presence of Zeiglar Natta catalyst or metallocene catalyst. Polypropylene. Thus propene (or propylene) is the monomer of polypropylene. Polypropylene is a highly flammable material. It is sensitive to microbial attacks, such as bacteria and mold. It exhibits excellent resistance to diluted and concentrated acids, alcohols and bases. Polypropylene is used to make lunch boxes, margarine containers, yogurt pots, syrup bottles etc. Disposable syringes is the most common medical application of polypropylene. Polypropylene rope and twine are very strong and moisture resistant very suitable for marine applications. Polypropylene, highly colorfast, is widely used in manufacturing carpets, rugs and mats. Uses of Polypropylene. Questions on polypropylene; Q1) What is polypropylene? Ans) Polypropylene is a polymer of propylen
Post a Comment
Read more

Difference between organic and inorganic polymers.

Difference between organic and inorganic polymers. Definition Organic polymers are the polymers that essentially contain carbon atom in the backbone. Inorganic polymers are the polymers that have no carbon atom in the backbone. Structure Most organic polymers have simple structures. Almost all inorganic polymers are highly branched and have complex structures. Electrical Conductivity In most of the aqueous solutions, organic polymers are typically poor conductors of electricity and heat. Inorganic polymers in aqueous solutions are good conductors of electricity, this is because they have high ability to ionise and this makes them better conductors. Flammability Organic polymers are flammable whereas inorganic polymers are nonflammable. Effect on nature Organic polymers are environmental friendly as these are biodegradable. Inorganic polymers are not environmental friendly as these are non biodegradable. Examples Organic polymers include polysaccharide
Post a Comment
Read more