Interior block resistance

ASTM D4946-89(2003) Standard Test Method for Blocking Resistance of Architectural Paints. ISO 15741 2001 Paints and varnishes — Friction-reduction coatings for the interior of on-and offshore steel pipelines for non-corrosive gases. 

AH-acryHc (100%) latex emulsions are commonly recognized as the most durable paints for exterior use. Exterior grades are usuaHy copolymers of methyl methacrylate with butyl acrylate or 2-ethyIhexyl acrylate (see Acrylic ester polymers). Interior grades are based on methyl methacrylate copolymerized with butyl acrylate or ethyl acrylate. AcryHc latex emulsions are not commonly used in interior flat paints because these paints typicaHy do not require the kind of performance characteristics that acryHcs offer. However, for interior semigloss or gloss paints, aH-acryHc polymers and acryHc copolymers are used almost exclusively due to their exceUent gloss potential, adhesion characteristics, as weU as block and print resistance. 

The characteristics of interior paints that require testing and analysis include hiding and appearance, package stabiHty, adhesion, spatter resistance, flow and leveling, color and sheen uniformity, touch-up, stain removal, burnish resistance, and block and print resistance. A popular test that assesses the wet abrasion resistance of an interior paint is to measure its scmb resistance. A mechanical device is used to scmb a paint film of a specified thickness with a standard bmsh and abrasive cleanser suspension. The number of scmb cycles (back and forth movements of the weighted bmsh) at various end points (first cut through, or 50% removal of the film) is then recorded. Scmb resistance usually holds steady or decreases slightly as PVC is increased, but drops quickly once the CPVC is exceeded in a paint formulation. 

Backcoating of upholstery fabrics, using decabromodiphenyl ether (deca-BDE) or hexabro-mocyclododecane, antimony trioxide, and an acrylic latex, is effective for flame resistance, but there are toxicity concerns. The use of synthetic barrier fabrics (i.e., interior fire-blocking) may remove the need for chemical backcoating. 

Structural tile can be used as a lining in a metal vessel similar to a brick lining, as shown in Figure 51-2, but is more commonly used to build relatively inexpensive reinforced concrete structures with corrosion resistant interior and exterior surfaces. Two different types of wall construction are shown in Figures 51-3 and 514. In Figure 51-3 the tile are used in their block form. The wall thickness is obviously limited by the width of the block. In Figure 514, the tile is split to construct a wall of any practical thickness. 

Cratons. Ancient crystalline terranes, forming extensive cratons and large tracts of continental interiors, are generally viewed as tectonically and isostatically stable, and resistant to internal deformation. A growing body of evidence however, based on reconnaissance apatite studies of different cratons and Precambrian blocks, has revealed discrete, regional episodes of Phanerozoic km-scale cmstal erosion of these ancient terrains (Crowley et al. 1986, 1991 Zeck et al. 1988, Brown et al. 1990, Noble et al. 1997, Spikings et al. 1997, Harman et al. 1998, Mitchell et al. 1998, Cederbom et al. 

Polyolefin (PO = PP, HOPE, EPR, or PMP) was blended with an impact modifier, 0.1-5 wt% colorant and/or 5-50 wt% of opadfios, and a styrene-diolefin block copolymer, grafted with 1-6 mol% of acrylic acid, maleic anhydride, or snlftniale functionality (SEBS, SEPS, radial SEB, or SEP). To improve scratch resistance the blend contained 100-3,000 ppm Zn stearate and 16-22C fatty acid amide. The alloys were injection molded into parts showing impact, scratch, and abrasion resistance. They were used to manufacture interior trim for vehicles and in other applications where a scratch- and scuff-resistant plastic material is required ... 

D-3024. Specification for Protein-Base Adhesives for Structural Laminated Wood Products for Use Under Interior (Diy Use) Exposure Conditions. Employs the D-0>905 block shear, D-0906 plywood shear, and D-4300 mold resistance tests to evaluate mostly casein-base adhesives for use in interior grade laminated beams. 

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