纺织品功能整理课件 (10)

The last group of non-durable antistats is noncomposed of non-ionic compounds such as nonethoxylated fatty esters, alcohols and alkylamines
internal antistatic agents, incorporated into the polymer matrix during the extrusion process
Antistatic agents that increase fibre surface conductivity form an intermediate layer on the surface. This layer is typically hygroscopic. The increased moisture content leads to higher conductivity. The presence of mobile ions on the surface is very important for increased conductivity. The effectiveness of hygroscopic antistatic finishes depends greatly on the humidity of the surrounding air during actual use; lower humidity leads to lower conductivity (higher resistance) and greater problems with static electricity.
10.5 Evaluation of antistatic finishes
Surface resistivity and practical use of antistatic finished textiles
Field intensity half-life time and practical use of antistatic finished textiles
10.3Chemistry of antistatic finishes
NonNon-durable finishes
• Nondurable antistatic agents are preferred for fibre and yarn processing finishes since ease of removal is important. • surfactants, organic salts, glycols, polyethylene glycols,polyelectrolytes, quaternary ammonium salts with fatty alkyl chains, polyethylene oxide compounds and esters of salts of alkylphosphonium acids.
Antistatic finishes
10
outline
10.1 10.2 10.3 10.4 10.5 10.6 Introduction Mechanisms of antistatic finishes Chemistry of antistatic finishes Conductive fibres Evaluation of antistatic finishes Troubleshooting for antistatic finishes and particularities
10.4 Conductive fibres
Electrically conductive fibres have been produced by several methods: Dispersing carbon particles or other antistatic agents in polymer melts prior to extrusion; depositing carbon (epitropic fibres) or metallic (for example nano-silver) coatings onto fibre surfaces (for example Ni, CuS) incorporating hydrophilic comonomers; and by fabricating fibres from stainless steel, aluminium or other metals.
10.2 Mechanisms of antistaLeabharlann Baiduic finishes
increasing the conductivity of the fibre surface (equivalent to lowering the surface resistivity)
reducing frictional forces through lubrication
10.1 Introduction
Causes of Static
• Static is defined as the surface build-up buildof electrical charges whenever two unlike surfaces contact one another.
Durable antistats
The basic principle is to form a crosslinked polymer network containing hydrophilic groups. Typically, polyamines are reacted with polyglycols to make such structures.
Esters of phosphoric acid form the largest group of nonnon-durable antistats
Quaternary ammonium compounds are the next largest group of non-durable antistats. non-
SOUTHERN YANGTZE UNIVERSITY SOUTHERN YANGTZE UNIVERSITY SOUTHERN YANGTZE UNIVERSITY SOUTHERN YANGTZE UNIVERSITY SOUTHERN YANGTZE UNIVERSITY SOUTHERN YANGTZE UNIVERSITY SOUTHERN YANGTZE UNIVERSITY SOUTHERN YANGTZE UNIVERSITY
Triboelectric series of textile fibres
Problems Caused by Static Electricity
Static can cause problems in the proper folding of long lengths of fabrics in the dye house. Dust can be attracted from the atmosphere to soil the textile. Static can cause garments to cling to the body, an aggravating consumer problem. Lint or other unwanted materials can be attracted to socks and pant legs from carpets and dusty floors.