Thixotropic adhesive gels

In thixotropic adhesive gels based on polyvinylalcohol, plasticizers are selected to maintain optical clarity of gel. " In some processes, plasticizers are nsed to process the... 

Uses Thixotrope, antisagging agent, antisettling agent for adhesives, sealants, gel coats, inks, and potting compels. 

A general purpose, preaccelerated, low reactive, LSE, thixotropic orthophthalic resin offering good interiaminar adhesion for hand-lay and spray/projection lamination. (Short gel time for spray lay-up.)... 

A preaccelerated, slightly thixotropic, general purpose resin exhibiting a long gel time and good interlaminar adhesion properties, for hand-lay and spray/projection lamination. 

The flow period must be long enough and at a viscosity sufficiently low for excellent wet-out of the substrate surface. However, if the flow period is too long, the adhesive will run beyond the edges and the bond line will be starved of adhesive. The optimum is to have a brief period of high flow, and then the adhesive must gel to hold its position. That is why most adhesives are formulated to be thixotropic (time-dependent shear thinning imder stress). 

Inorganic fillers are not widely used due to the likely instability which would be caused by these materials. Recently, stable thixotropic gels (see the section on Recent Advances) which can be applied to vertical or overhead surfaces have been prepared by Loctite. These materials are prepared from silane-treated hydrophobic silicas which are drier and considerably more stable than conventional silicas in cyanoacrylate adhesives.The bond properties of these gels are identical to the flowable Newtonian cyanoacrylate adhesives. 

Thermosetting adhesives are typically available in liquid, paste, and solid forms. The liquid form is generally one- or two-part system which may contain solid fillers and colorants. The paste form typically exhibits flow behavior different from those of the unfilled or highly filled liquids. Certain pastes are modified to be thixotropic, which are gel-like materials at rest but act as fluid when agitated. Possession of such solid-like yielding behavior allows an unstrained mass of adhesive not to sag or flow unless forced to do so by mechanical action, such as by spreading with a spatula. 

UV acrylic formulations cure to form thermoset resins and can provide a variety of properties from extremely flexible (>250% elongation) to very hard and rigid with a high modulus. The UV adhesives are offered in a selection of viscosities from thin liquids (less than 100 mPa-s) to highly thixotropic gel consistency with a viscosity greater than 50,000 mPa-s - making them suitable for a wide range of applications. 

Uses Thickener, water binder, flow aid, thixotrope, suspending agent, gellant, foam stabilizer, adhesion promoter, lubricant in toothpaste, denture adhesives, hair dyes, liq. makeup/mascara/eyeliner thickener in hydrocolloid wound gels absorbent for body fluids in dressings Blemmer50PIEP-800B [NOF]... 

Uses Foam stabilizer, flocculanl suspending, gelling agent, rheology modifier, lubricant for industrial applies, incl. abrasives, adhesives, herbicides, fertilizers, ceramics, cleaners, emulsions, gels, mining, thixotropic paints, paper, petrol., pigments... 

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