STAIN RESISTANCE

Physical Properties. Table 1 (2) shows that olefin fibers differ from other synthetic fibers in two important respects (/) olefin fibers have very low moisture absorption and thus excellent stain resistance and almost equal wet and dry properties, and (2) the low density of olefin fibers allows a much lighter weight product at a specified size or coverage. Thus one kilogram of polypropylene fiber can produce a fabric, carpet, etc, with much more fiber per unit area than a kilogram of most other fibers. 

Mechanical Properties. The stain resistance of paints is directly related to their porosity. Therefore fillers that help to reduce porosity, ie, those with low surface areas, wide size distribution, and laminar shapes, contribute to stain resistance. 

Often used as mixtures, the telomers are subsequently converted to commercial surfactants and stain-resistant fiber finishes through functionalizing steps using standard chemical reactions of the C—1 bond. 

A comparison of coatings formulations based on various glycols to determine the effects of the various glycol stmctures on the performance properties of the coatings has been made. Properties compared included degree of cure, flexibiHty, hardness, hydrolytic stabiHty, processibiHty, chemical and stain resistance, and viscosity (18,19). 

Aesthetic properties are of greatest concern in decorative laminates. These include gloss, appearance, cleanabiUty, wear resistance, stain resistance, and other surface properties. Physical properties are of most importance for industrial laminates. These include strength, electrical and thermal properties, expansion coefficient, and punchabiUty. The definitions of the laminate grades in these standards foUow. 

Fibers. Polypropylene fibers are extensively used in carpeting. Bulked continuous filament yams are commonly used in carpet facing in the level loop carpets used in commercial buildings however, nylon remains the dominant face yam in tufted household carpets. The advantages of polypropylene carpeting are superior stain resistance and low moisture absorbance. Polypropylene sHt tape fibers are heavily used in carpet backing. 

Silicones. SUicones are exceeded only by fluorochemicals in the volume used as repeUents for textiles. They are widely used on ceUulosic and synthetic fiber fabrics. SUicones provide water-based stain resistance good durabUity to washing improved tear strength a soft, sUck hand and improved fabric sewabUity. 

Carpet. Carpet, an important textile, may also be treated to provide water and oU repeUency however, the principal functions of the current carpet treatments are to provide soU and stain resistance. High quaUty carpets, especiaUy those made from nylon, polyester, or wool, have a significant proportion of the surface coated with fluorochemical materials. The treatments can be spray-appUed to a finished carpet or appUed directly to the fiber during the spinning or dyeing operations. Suitable fluorinated resin materials are readily avaUable from 3M or DuPont. 

Chrome complexes of stearic and myristic acids provide water and aqueous stain resistance, dimensional stabUity, and lubricity. The products may also enhance the appearance and durabUity of leather. The chrome complex reacts with the leather molecules to form a permanent bond. 

In the 3M Water/Alcohol Drop Test (41), this test is designed to provide a simple, rapid method to assess the aqueous stain resistance of substrates treated with a protective finish. 

Gold [7440-57-5] Au, is the principal constituent of gold-colored alloys. It contributes gold color kicreases the specific gravity raises the melting pokit, if that of the alloy is below that of gold and kicreases ductihty, maHeabiUty, corrosion, and stain resistance. Gold produces heat-treatable compositions with copper, platinum, and zkic. It is useful ki amounts of 25—100 wt %. 

One significant development in recent years has been the widespread treatment of clothing fabrics to give a measure of water and stain resistance. Mention may also be made of the expression Teflon-coated (Teflon is the DuPont trade name for PTFE) to describe a person, usually a politician, to whom no dirt (i.e. scandal) sticks, a reflection of the non-stick characteristics of the polymer ... 

The principal application of melamine-formaldehyde moulding compositions is for the manufacture of tableware, largely because of their wide colour range, surface hardness and stain resistance. The stain resistance does, however, leave something to be desired and one aim of current research is to discover alternative materials superior in this respect. Cellulose-filled compositions also find a small outlet for trays, clock cases and radio cabinets and other purposes. The mineral-filled powders are used in electrical applications and knobs and handles for kitchen utensils. 

Cadmium is more expensive than zinc. It is usually applied by electrodeposition in thicknesses up to about 25 tm and has a superior tarnish and stain resistance to that of zinc. As with zinc, the life of cadmium coatings is proportional to thickness Hudson quotes a life of only 9 months at Sheffield for a 25 m thick coating and approximately 8 years for a 42 m thick coating exposed to a marine environment at Calshot. 

Aminoplastics In this group, melamine-formaldehyde resins with their good heat resistance, scratch resistance and stain resistance, are usually preferred to urea-formaldehyde resins where chemical resistance is important. Unlike the phenolics these materials are not restricted to dark colours. 

These copolymers have been mentioned already in section 10.10.4 as versatile and highly effective stain-resist, oil- and water-repellent finishing agents. 

Surface Modifications. Basic photopolymer chemistry is also being used for the surface modification of films, textiles fibers, and many other organic-based materials (104). Some of the novel applications of photopolymer technology to surface modification include the design of cell repellent treatments and in photografting of various chemical functionality onto the surface of materials to improve color retention, enhance the adhesion of antistatic chemicals or to improve staining resistance. 

Nylon blends, dyeing, 9 204 Nylon block copolymer, 19 762 Nylon carpet fibers, stain-resistant, 19 764 Nylon-clay nanocomposites, 11 313-314 Nylon extrusion, temperatures for, 19 789t Nylon feed yarns, spin-oriented, 19 752 Nylon fiber(s), 24 61 production of, 19 740 world production of, 19 7654 Nylon fiber surfaces, grafting of polymers on, 19 763-764... 

PVF films are appreciated for weatherability, good chemical and staining resistance good non-stick properties, easy-to-clean properties low permeability good behaviour at low temperature good electrical insulating properties even in hot and wet environments fire resistance (but beware of toxic fumes). 

DuPont and Shell have developed a new polyester, poly(trimethylene terephthalate) (PTT) (structure 19.38) that is structurally similar to PET, except that 1,3-propanediol (PDO) is used in place of ethylene glycol. The extra carbon in Sorona allows the fiber to be more easily colored giving a textile material that is softer with greater stretch. Further, it offers good wear and stain resistance for carpet use. The ready availability of the monomer PDO is a major consideration with efforts underway to create PDO from the fermentation of sugar through the use of biocatalysts for this conversion. Sorona and Lycra blends have already been successfully marketed. Sorona is also targeted for use as a resin and film. 

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