Page 566 - Handbook of Thermal Analysis of Construction Materials
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536                    Chapter 13 - Organic Construction Materials


                              resin to modify their properties and, most of all, reduce cost. Most fillers are
                              minerals; they reduce cost, provide speed of cure; add strength; and provide
                                                                              [3]
                              special electrical, mechanical, and chemical properties.  The combination
                              of the polymer (thermoplastic, thermoset, elastomer) and reinforcing-fiber
                              materials such as glass or carbon results in a material known as a composite.
                              A wide range of crystalline and amorphous materials can be used as the
                              fiber. Carbon black and glass fiber are commonly used in the fabrication of
                              construction materials, e.g., roofing.
                                     There is a strong interaction between the three major construction
                              sectors: the building industry, the building materials manufacturers, and the
                              industrial mineral producers who supply many of the raw materials to make
                              the building products. Therefore, any changes in the construction industry
                              and technological advances in building products and construction methods
                              could have a potential impact in any of these sectors. [7]
                                     Most of the construction materials are derived from four major
                              sources: forest products, metal fabrication, chemical products, and indus-
                              trial minerals. Wood, as a forest product, has many applications, e.g., as a
                              fuel, construction materials, in weapons, and transportation. As the science
                              of engineering developed, wood was replaced by other materials. However,
                              there has been a tremendous increase in the number and variety of products
                                                                       [8]
                              made either directly or indirectly from wood.  There is a diversity of
                              products used in construction, which are derived from industrial minerals
                              such as portland cement, calcium carbonate, and fillers. Similarly, stone in
                              one form or another has been an important construction material from early
                              time. For example, internationally, the great ages of stone construction have
                              reflected the wealth of societies. Modern construction uses cut natural stone
                              for the structural fabric and decoration of many buildings.
                                     Natural chemical products and polymer-based (e.g., asphalt) mate-
                              rials have been part of building construction. Their applications range from
                              the reinforcement given by natural fibers to the use of resins as adhesives.
                              As a result of new trends in the construction industry, there has been a major
                              increase in the use of synthetic polymers such as adhesives, sealants, paints,
                              coatings, insulation materials, and plastics. Since these polymers contain
                              carbon, they are also called organics. Examples of their applications are
                              given Table 1.
                                     The large increase in the use of polymer-based materials in the
                              construction industry is due to the fact that they have certain advantages
                              over mineral materials. For example, they are lightweight; can be welded;
                              cut and glued in rapid, automated processes; and are unlike cement-based
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