Properties of textile fibres. (Part 1)

Properties of textile fibres

Electrical properties

Fibres are usually not used in electrical application, however their property of great interest is their resistivity. Too high resistivity leads to the development of static charge, which cause the fabric to cling and to be difficult to clean.

Mechanical properties

The mechanical properties of fibre are quite complex. The stressed textile fibre is a visco-elastic complex system in which number of irreversible process takes place. On the basis of fibre stress strain curve, it is divided into two types; silk like curve and wool like curve.

Moisture regain

The moisture regain of synthetic polyesters, nylon and acrylics are lower than that of natural fibres, that the synthetics are classed as hydrophobic materials. This is an advantage for rapid drying.

Dyeability

The hydrophobic materials are difficult to dye. Acrylics are bad in this respect. Polyesters and nylon are intemediate in dyeability. While cellulose and cellulosic fibre are eminently dyeable.

Chemical stability

The fibre must be stable with water, drycleaning solvents, alkalies, dilute acids and bleaches. Silk and nylon are the least satisfactory fibre in veiw of standing to weatherability, while acrylics are most stable in this respect.
Properties of textile fibres part 2

Comments

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

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

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

Polymers

Search This Blog