Sealant spacer

In order to produce the uniform cell gap by pressing the glass substrates, rigid particles are incorporated in the sealant. For this purpose, the silica spacer or the glass fiber spacer, both characterized by high compressive moduli, is used. In this case the spacer is called sealant spacer or edge spacer . Thus, sealant spacer plays a role of pillar for resisting... 

In the constmction industry, ceUular polymers are used as spacers and sealant strips in windows, doors, and closures of other types, as weU as for backup strips for other sealants. 

Prior to application of the composite, the concrete surface was sandblasted, washed with a 10% hydrochloric acid solution, rinsed with water, and dried. This ensured good adhesion to the fresh concrete surface. Spacers were placed directly over joints in the concrete and were removed after the coating was applied. The resulting joints were caulked with an acid-resistant sealant. 

Insulating Glass Sealant - (Forms structural seal to bond pieces of glass and spacer first high performance organic seal)... 

The epoxy specimens were cured in disposable fluorescence/transmission cells (Fig. 2) made from two microscope-slide glass plates cut to fit the width and height dimensions of the standard cell holder (12 x 45 mm) with a light path of 1.5 mm determined by the thickness of a silicone rubber spacer/sealant strip. 

Insulating glass or double glazed units consist of two panes of glass separated by a spacer and all are held together by edge Sealants (Fig. 1). These sealants seek to exploit the specific properties of low moisture vapour transmission, low inert-gas transmission and high durability of the sealant used (see Durability fundamentals). 

A practical use of Saret 633 as an internal adhesion promoter is shown in Table 8.13 which gives a formulation for a pumpable sealant based on liquid EPDM [24]. This formulation not only gives excellent adhesion to steel, but bonds strongly to oily steel as well. In this example, lap shear adhesion was determined using steel coupons, overlapped 2.5 cm, with a spacer to form a uniform sealant thickness of 0.18 cm. Light pressure was applied so that the upper coupon would be pressed against the spacer. The sealant was then cured at 160 °C for 25 minutes. To test for bonding to an oily surface, the steel... 

Lap shear adhesion was measured using steel coupons overlapped 2.5 cm. Spacers were used between the coupons to obtain a uniform sealant thickness of 0.18 cm. Light pressure was applied so the upper coupon would bear evenly on the spacers. The sealant compounds were then cured at 160 °C for 25 minutes and then tested at room temperature. 

Applications " cling film, glazing spacers, roofing membranes, sealants, transdermal administration of hypermic active substances ... 

LCD spacer has two kinds of usage. Spacer particles used in a display portion is called cell spacer or sinply spacer . Another use pf spacer particle is for an epoxy-sealant which encloses liquid crystals in a LCD cell as shown in Figure 8-1. 

An example of photographs of silica spacer particles dispersed in the sealant is shown in Figure 8-4, in order to obtain a general idea on the particle-size distribution and dispersion in sealant. 

Figure 8-4. Example of silica spacers dispersed in the sealant of a LCD cell...

A typical construction involves a combination system employing a butyl mastic as the barrier sealant between the metal spacer and glass and a back-up, chemically curing sealant serving as an adhesive to hold the unit together. An insulated glass mastic formulation is shown in Table 14. Vistanex LM low molecular weight PIB is combined with a platy talc filler... 

Extruded Tapes. These are preformed ribbons or profiles of butyl rubber, neoprene, or polyvinyl chloride, and may be either solid or expanded. They may be supplied as composite structures with rubber cores, rubber rod spacer, or aluminum shims surrounded or embedded in an adhesive or sealant. 

Preformed Tapes. Preformed tapes of butyl, usually vulcanized, are extruded semisolid sections with pressure-sensitive adhesion. Since they are 100% solid, there are no problems of shrinkage or solvent evaporation. Sold in rolls interlined with release paper, they are often used together with liquid sealants or solid spacers, shims, etc. They vary from low cost, highly polybutene-extended tapes for trailers and mobile homes, to partially or fully vulcanized butyl rubbers with little polybutene content for high-rise glazing and automotive windshield sealants. 

In all adhesive and sealant apphcations the aim is to apply a uniform layer of material of the appropriate thickness across the entire area to be joined to achieve the optimum performance. In many manual or semiautomatic applications this is achieved by using spacers or jigs to control product thickness. Pressure fed application equipment is also often utilized to ensure... 

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