Non-load bearing applications

The group of rigid cellular polymers can be further subdivided according to whether they are used (1) for non-load-bearing applications, such as thermal insulation or as (2) load-bearing structural materials, which require high stiffness, strength and impact resistance. 

The CTH approach also has some other differences as compared to SMASH. For example, the SMASH approach focuses on non-load-bearing applications such as self-healing bladders, inflated structure membranes, architectural building envelopes, and coaling [52,54]. On the other hand, the CTH approach focuses on load bearing structures. It also considers the boundary conditions to be encountered in real structure applications, as discussed above. 

These are the least costly resin materials used in hot melts. Their applications include bonding paper, cardboard, wood, fabric, etc., for use at -34°C to 49°C. Compounded versions can be used for non-load-bearing applications up to about 71°C. EVAs and polyethylenes represent the highest volume of hot-melt adhesives used, primarily in packaging and wood-assembly applications. ... 

These compounds are the next stop up in strength and general service in hot-melt adhesives. These so-called high-performance hot melts are used to assemble products made from glass, hardboard, wood, fabric, foam, leather, hard rubber, and some metals. Service temperatures range from 0°C to about 82°C. A number of formulations are available that can be used at >93 °C. Some are capable of being used in non-load-bearing applications at>149°C. ... 

These are a number of non-load bearing applications of polymers, and their use is more common in housing construction. These non-load bearing secondary structural or non-structural applications can be categorised in four main areas ... 

Since up to 80% of the AACs volume consists of air, these materials have very low densities, which in turn accounts for their low compression strengths of, at most, lOMPa (compared to about 100 MPa for ordinary concrete). Despite such a low compressive strength, AACs are used at construction sites worldwide for non-load-bearing applications. In particular, AACs are seen as an environment-friendly materials, for reasons that include ... 

However, one of the major setbacks of HA is the poor mechanical properties inherited by the sintered body [6], Owing to the brittle nature and the low fracture toughness (< 1 MPam ) of the sintered HA, such implants could only be utilised successfully in non-load bearing applications [7], Therefore, the development of bioactive HA that has improved and ultimately bone-like mechanical properties are desirable. As a result, a great number of studies have been devoted to improve the mechanical properties of HA materials [4-8],... 

Al-Mn. A cheap, non-heat-treatable alloy of poor mechanical properties, fair castibility, but exceptional for non-load-bearing applications at temperatures of up to 500°C (for instance, gas burners of domestic cookers). 

Silica-based BGs are a group of surface-reactive glass-ceramic (GC) biomaterials, first prepared by Hench et al. in 1969 [38]. BGs possess excellent biocompatibility, the ability to bond with bone and other tissues and stimulatory effects on bone ceU function [39 1] which explain their successful application as bone-substitute material for non-load-bearing applications in orthopaedic and dental surgery [41,42],... 

The material used in this technique is conventional concrete and epoxy resin bonding agent. The concrete should be the same as the old concrete but with consistency (slump value) within 40 mm. The resin should be of two components, 100 % solid type, meeting the requirements of specification ASTM C-881 (2010) for type II or type V, class B or C (depending on the ambient temperature). Type II can be used for use in non-load-bearing applications to bond fresh to hardened concrete, while for load-bearing applicatimis, type V should be used (ASTM C-881 2010). 

This specification applies to faced or unfaced, rigid cellular phenolic thermal insulation in either board or tubular form. Materials covered are used as roof insulation, sheathing or rigid board for non-load bearing, building material applications, and pipe insulation between -40° and 125°C (-40° and 257°F). 

Good processability may be required in fabrication operations such as injection or blow molding, extrusion and thermoforming. High mechanical performance may not always be needed in non-load bearing simations. Examples of PAB s for various electrical applications are shown in Table 13.11. 

Weight reduction is a powerful incentive in aircraft manufacturing. Every kilogram of structure that can be eliminated facilitates a commensurate reduction in fuel consumption and therefore cost, or a commensurate increase in payload at equal fuel cost. Hollow glass fibers qualify for use in non-load bearing interior aircraft applications such as sidewall and ceiling panels. The use of hollow glass fibers for such applications are more prevalent in Russia and CIS countries [53] than in the United States and the Western world. 

These fibers can be used from room temperature to 1000 C, but because of their ultralow strength, only in non-load bearing end uses. Pristine fiber strength deaeases from room temperature (0.4 GPa) to 1000°C (0.1 GPa). Application of a chromium oxide coating... 

Non-load bearing (non-structural foams) applications, snch as thermal insulation, or... 

Polypropylene and nylon FRC have been applied to non-structural and non-primary load-bearing applications. They are commonly employed in residential, commercial, and industrial products, such as slabs for composite metal deck construction, floor overlays, shotcrete for slope stabilization and pool construction, precast units, slip form curbs, and mortar applications involving sprayed and plastered Portland cement stucco (Krenchel and Shah, 1985 Zollo and Hays, 1991). 

Chitosan, a copolymer of 2-amino-2-deoxy-D-glucopyranose and 2-acetamido-2-deoxy-D-glucopyranose units, and alginate, a linear copolymer of b-(l,4)-linked D-mannuronic acid and a-(l,4)-linked L-guluronic acid units, have been spun into useful fibers. However, because of low mechanical properties they are mostly limited to medical and other non-load-bearing specialty applications [58]. Further information about chitosan fiber can be obtained elsewhere in this book. 

Foamed polymeric materials are produced in a wide range of bulk densities that mainly determine their mechanical properties. A high-density foam that has an improved tensile strength and modulus can be used for load-bearing applications, such as structural parts, while a low-density foam can be used in thermal insulation and packaging applications. In addition to the foam density, the size and distribution of cells also affects the final properties of the foam. Conventional plastic foams have relatively poor mechanical properties because the cell size is typically larger than 100 /xm and the cell size distribution is very non-imiform. In general, foams with very fine cell size exhibit better mechanical properties. 

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