Reinforcement with glass beads

Roofing panels have been made from polyisocyanurate foams, both foam- and felt-reinforced with glass fiber. Phenolic resins are used especially for decorative laminates for paneling. The substrate may be fiberboard or a core of expanded polystyrene beads. In one case the beads are coated with phenolic resin, then expanded in a mold to form a structural foam panel. 

Miscellaneous uses include textile bobbins, guns for hot melt adhesives and bilge pump housings. These materials are normally found in reinforced form. In addition to glass fibres, other fillers such as glass beads, talc and mica are used in conjunction with coupling agents. 

Glass beads act as a mineral filler with an aspect ratio of 1. Table 3.6 displays results for glass bead reinforced polyamide. The effect ratio is the performance of the reinforced polymer divided by the performance of the neat polymer. 

Silica powder, glass beads and fibres are commonly used for the reinforcement of plastics. The produced composite materials have an increased thermal and mechanical stability, compared to the pure polymeric material. In order to bind the inorganic filler to the organic matrix, silane molecules, with both an inorganic and organic side, are used. The silane may be mixed with the matrix and filler material in the composite preparation, or be coated onto the filler prior to mixing. The application... 

Nonfibrous reinforcements are also employed as reinforcements and fillers. They result in increased tensile strength and deflecdon temperature, but usually decrease impact resistance. Nonfibrous reinforcements are preferred when fabricating with exceptional flatness. The nonfibrous include mica, glass beads, and minerals such as wollastonite (talc, calcium carbonate, and kaolin are considered fillers). Unlike fibrous reinforcements the nonfibrous reinforcements can be processed by many different technologies. 

Interaction with the matrix (untreated calcium carbonate in PE decreases tensile strength but after phosphate modification tensile strength is increased glass beads may decrease or increase tensile strength depending on their interfacial adhesion mica and talc give a similar effect in PP polyamide fiber does not reinforce natural rubber because of its lack of interaction)... 

It has now been shown that recent studies of relaxation, sorptive, and diffusive behavior in many filled polymer systems amply confirm earlier observations of deviations from values predicted by simple additivity (Kumins, 1965). Such effects are not confined to high-surface-area fillers such as certain carbon blacks and fillers (typical reinforcing fillers for rubber) they are also observed frequently with low-surface-area fillers, such as pigments and even glass beads with average diameters in the range of tens of micrometers. 

Engineering polymers also include combinations or composites of the polymers listed in Table 1.1 with reinforcing agents such as glass fibre, talc, carbon fibres, clay minerals, mica and fillers such as calcium carbonate, glass beads, silica, lubricants, PTFE, silicones and molybdenum disulfide. 

Engineering polymers, such as PP can be reinforced at the macroscopic level with a variety of higher modulus materials such as fibres, beads, and cement, to form heterogeneous composites [4,5]. Thus, reinforcing PP with glass fibres as a co-woven mat has many advantages. Alternatively, reinforcement can also take place at the molecular level. These researchers have reported on the benefits of simultaneous... 

Other multiphase systems involving polymers include composite materials produced by mixing polymers with filler particles in order to modify their mechanical properties or conductivity. Typical additives include carbon black, clay, silica, and glass beads/fiber and understanding the interactions between the filler and the polymer matrix has implications for the performance of such materials. For example, carbon black has been used extensively as a reinforcing filler in a number of applications such as automotive tires and can also be blended with insulators such as semicrystalline PF to produce conductive composites used in electrical products. 

Let us now consider some experimental data on the influence of the interphase on the viscoelastic properties. One of the most convenient ways to study the problem is to use some model composites, consisting of the reinforcement covered by polymer, modelhng the interphase layer, and polymer matrix. The system epoxy resin-glass beads covered with poly(butyl methacrylate) was... 

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