Advantages of "polyurethane elastic fiber" material

Advantages of "polyurethane elastic fiber" material:

1, outstanding high toughness. The high resilience of spandex is incomparable to all elastic fibers at present. Its elongation at break is more than 400%, and the highest can reach 800%. Even at 300% stretching, the rebound recovery rate is still above 95%.

2. Excellent tensile strength and tear strength;

3. Strong weather resistance and ultraviolet radiation resistance;

4. Chemical resistance and washing resistance;

5. Good affinity with dyes.

Polyurethane elastic fiber, also called polyurethane fiber, is called spandex in China.

Composition structure:

Synthetic fibers made of polyurethane by dry spinning or wet spinning. It has high elastic recovery and elongation at break similar to rubber thread, and the elastic elongation is as high as 400% ~ 700%. When the elongation is 500% ~ 600%, the elastic recovery rate is 97% ~ 98%, but the strength is low, only 8.8cN/dtex.

Features:

Polyurethane used in fiber manufacturing is a block copolymer of polyester or polyether with hydroxyl group at the end and aromatic diisocyanate. It consists of flexible long chain segments (soft chain segments) and rigid short chain segments (rigid chain segments) alternately. The soft segment is low molecular weight polyester or polyether segment, which has no crystallinity and is easy to deform when stressed, so that the prepared fiber can be stretched and deformed; The rigid segment is an aromatic diisocyanate segment with crystallinity and transverse cross-linking, which does not deform under stress and can prevent transverse sliding, so that the prepared fiber has sufficient resilience. The content of soft segment in polyurethane fiber segment structure is generally not less than 80% ~ 85%. According to the composition of soft segment, it can be divided into polyester type and polyether type. Dupont Company of the United States produces polyether type and synthetic rubber company of the United States produces polyester type.

Polyurethane is dissolved in an organic solvent such as dimethylformamide, dimethylacetamide or dimethyl sulfoxide to obtain a spinning solution, which is spun into fibers by dry spinning or wet spinning, and then passed through an aqueous solution containing aliphatic diamine chain extender to obtain elastic polyurethane fibers.