Sealant latex

Silicones. Commercially avaHable sHicone sealants are typicaHy one of three curing types moisture-reactive (curing) sealants, moisture-releasing (latex) sealants, and addition-curing sealants. Of these three types, moisture-curing sHicones make up the vast majority of sHicone sealants sold. 

Table 5. One-Part Pigmented Siliconized Acrylic Latex Sealant ...

Table 6. One-Part Clear Acrylic Latex Sealant Formulation ...

M. A. Shewia, "High Performance AcryUc Latex Sealants," ia Ref. 9. 

One-part clear acrylic latex sealant formulation, 22 42t One-part manganese dioxide-cured polysulfide formulation, 22 4 It One-part pigmented siliconized acrylic latex sealant, 22 42t One-part RTV silicones, 22 596 One-part silicone cross-linkers, 22 33t One-part silicone sealant formulation, 22 34t... 

Silicone industry, history of, 22 547—548 Silicone latex sealants, 22 34—35 Silicone liquid-injection-molded (LIM) rubber... 

M. A. Shewin, "High Performance Acrylic Latex Sealants," in Ref. 9. 

The formulation ofmoisture-ujriiig silicones includes a silicone polymer, filler, a moisture-reactive cross-linker, and sometimes a catalyst. A newer class of silicone sealants are known as the silicone latex sealants. These sealants are silicone-in-water emulsions that cure by evaporation of the emulsifying water. Addition-curing silicones in general are two-part systems that cure by the platinum-catalyzed reaction of a silicone hydride with typically a vinyl group attached to silicon. Because no by-products are generated by the cure, there are few volatiles and no shrink in thick sections. 

Acrylics. There are two principal classes of acrylic sealants latex acrylics and solvent-release actylics. High molecular weight latex acrylic polymers are prepared by emulsion polymerization of alkyl esters of acrylic acid, The emulsion polymers are compounded inlo sealants by adding fillers, plasticizers, freeze-thaw stabilizers, thickeners, and adhesion promoters. As is true of the silicone lalex sealants, die acrylic latex sealants are easy to apply and clean with water. 

Acrylic latex sealants. Basic acrylic latex sealant formulations were compounded in a sigma blade mixer, as shown in Table 3. The water-borne silanes were then incorporated into a base. Standard wet and dry peel adhesion determinations from various substrates were performed periodically in accordance with ASTM C794-8. 

Acrylic latex sealants. Adhesion strengths on three substrates after 3 months sealant storage (0.5% silane added) were evaluated and the results are presented in Table 4. 

A black-and-white felt rub-down test is performed to demonstrate adequate cleanliness of the interior clean-envelope surfaces. This test consists of both black-and-white felt being wiped over any surface for 1 m linear distance with a firm hand pressure. No residue should be visible on the cloth. Each cloth should be 60cm square black or white static-free natural hber felt folded with cut edges inside to a 25-cm square. The cut edges should be sealed with an approved latex sealant. 

Water-based acrylic sealants are also referred to as acrylic emulsion sealants or latex sealants. These are one-component gun-grade material with a solid content ranging from 80%-85%. Curing occurs by evaporation... 

C731 Test method (TM) for extrudability, after package ageing, of latex sealants. 

C-732 TM for ageing effects of artificial weathering on latex sealants. C-733 TM for volume shrinkage of latex sealants. 

Acrylam i do-2-methyl propanesulfonic acid protective colloid, acrylic/modified acrylic latex sealants... 

Acrylamido-2-methylpropanesulfonic acid surfacknt, acrylic/modified acrylic latex inks 2-Acrylamido-2-methylpropanesulfonic acid surfactant, acrylic/modified acrylic latex paints 2-Acrylamido-2-methylpropanesulfonic acid surfactant, acrylic/modified acrylic latex sealants... 

This paper reports on the synthesis, characterisation, and applications of novel flame retardant dibromostyrene-based latexes. They are copolymers of dibromostyrene with butadiene, alkyl acrylates and methacrylates, vinyl acetate, styrene and unsaturated carboxylic acids, which form a wide variety of flame retardant latexes via an emulsion polymerisation technique. Choice of monomer or monomer blend is based upon the final glass transition temperature of the copolymer desired. Other criteria include desired physical properties and chemical resistance. Dibromostyrene-based butadiene and acryUc latexes are shown to possess the desired physical properties for use in coatings, adhesives and sealants, and the bromine content of the latexes has enabled the material to pass six different flammability requirements for the end uses such as textile backcoating, latex-based paint, contact adhesive, latex sealant, nonwoven binder, and carpet backing. 18 refs. 

ASTM C 732 [395] Standard Test Method for Aging Effects of Artificial Weathering on Latex Sealants... 

ASTM C 734 [396] Standard Test Method for Low-Temperature Flexibility of Latex Sealants After Artificial Weathering... 

Cyanoacrylate Adhesives Anaerobic Compounds Epoxies Industrial Sealants and Adhesives Construction Silicones Construction Polyurethanes Latex Sealants Firestop Products Pool Spa Sealants Silicone Greases and Compounds Aerosols Cleaners... 

Medium movement sealants show versatility. Latex sealants offer compatibility with latex paint in that they are suitable for coating and provide ease of cleanup. This allows them to be used as an interior sealant under paint finishes. Butyl sealants have good adhesion to most surfaces and good resistance to water. This leads to their use in such places as door thresholds, flashing, metal and vinyl siding, and duct end pipe penetrations. 

Test for adhesion and cohesion of elastomeric joint sealants under cyclic movement Test for extrudability after package aging of latex sealing compounds Test for aging effects of artificial weathering on latex sealing compounds Test for volume shrinkage of latex sealant compounds... 

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