Laminates, cloth

The thermosetting materials are said to be initially linear but are cross-linked by heating in air to a temperature of at least 345°C. It is claimed that they have a useful working range up to 315°C. The materials may be used in compression mouldings powders, as the binder resin in glass cloth laminates and as the polymer base in heat-resistant metal coatings. 

Two classes of resol are generally distinguished, water-soluble resins prepared using caustic soda as catalyst, and spirit-soluble resins which are catalysed by addition of ammonia. The water-soluble resins are usually only partially dehydrated during manufacture to give an aqueous resin solution with a solids content of about 70%. The solution viscosity can critically affect the success in a given application. Water-soluble resols are used mainly for mechanical grade paper and cloth laminates and in decorative laminates. 

Property Hand lay-up mat laminate Press formed mat laminate Fine square woven cloth laminate Rod from rovings... 

Table 26.11 Mechanical properties of epoxy-glass cloth laminates...

Figure 29.4. Influence of resin content on the flexural strength of glass-cloth laminates made with two silicone resins A and B. (After Gale " )...

Of particular importance are the electrical properties of the laminates. These are generally superior to P-F and M-F glass-cloth laminates, as may be seen from Table 29.3P... 

The power factor of typical glass-cloth laminates decreases with aging at about 250°C, which is the main reason for post-curing (Figure 29.5). A power factor drift is, however, observed - under wet conditions and the ratio of power factors between wet and dry conditions is about 3 1. 

Figure 29.5. Effect of aging at 250°C on the power factor of silicone-bonded, glass-cloth laminates.

Phenolic phenol formaldehydes (PFs) are the low-cost workhorse of the electrical industry (particularly in the past) low creep, excellent dimensional stability, good chemical resistance, good weatherability. Molded black or brown opaque handles for cookware are familiar applications. Also used as a caramel colored impregnating plastics for wood or cloth laminates, and (with reinforcement) for brake linings and many under-the-hood automotive electricals. There are different grades of phenolics that range from very low cost (with low performances) to high cost (with superior performances). The first of the thermosets to be injection-molded (1909). 

The design of sensitive elements (transducers) is based on the conductive principle of response registration the output signal appears to depend on the conductive properties of the TCNQ compound as a result of its interaction with gas components. The gas-sensitive substance of the transducer has been manufactured from complex TCNQ salts with N-alkylisoquinoUnium cations ([N-C H -iso-Qn] (TCNQ)Q [26]. The substance of the gas sensitive layer is put in contact with copper or silver current feeding electrodes, put on the dielectric substrate manufactured from glass-cloth laminate. 

Phenolic glass cloth (laminate) Carbon steel Common glass High-nickel cast iron... 

The materials tested were mainly unidirectional and bidirectional satin cloth laminate. Unsaturated polyester resin was used as a matrix. The tensile strength ratio of longitudinal fiber to transverse fiber was... 

The temperature dependence of the absorbed energy for standard specimens is shown in Figure 1. Impact behaviors and fracture modes of edge notched specimens depending on temperature were reported elsewhere (9, 10). In edge notched specimens of unidirectional roving reinforced material (GC 68 wt % ), cloth laminates, and mat reinforced material the fracture mode changed with temperature all materials re-... 

Figure 2. Variation of static tensile and compressive strength of cloth laminates with temperature...

Tough—Brittle Transition in Cloth Laminates. For cloth specimens notched edgewise transition of fracture mode occurred with a variation of specimen size although the law of similarity held for each region having the same fracture mode. Figure 5 shows this transition for bidirectional cloth specimens at room temperature. With the increase of remain-... 

Figure 7. Appearance of fracture surface with variation of specimen width for bidirectional cloth laminate...

Figure 8. Effect of specimen size on absorbed energy of unidirectional cloth laminate at room temperature...

Figure 11. Relationship between transition in fracture mode and critical size ratio for unidirectional cloth laminate...

These new composites are stronger than the old polyester resin/"E" type fiberglass cloth laminates. 

MIL-C-43858B(GL) Cloth, Laminated, Nylon Tricot, Pblyurethane Foam Laminate, Chemical Protective and Flame Resistant, 16 January 1986, 25 pp (FSC 8305) (GL)... 

Covers three types of tricot knit nylon cloth laminated to a polyester-base polyurethane foam and impregnated with an activated-carbon mixture. 

A four-ply graphite cloth laminate based on polymer (e) was fabricated. Limiting oxygen index of this laminate was determined according to ASTM D2863-74 and was found to be 71%. Similar values for the graphite cloth laminates fabricated from 9,9-bis(p-maleimidophenyl)fluorene have been obtained earlier (2). 

Molded black or brown opaque handles for cookware have been familiar applications. Also used as a caramel colored impregnating plastics for wood or cloth laminates, and (with reinforcement) for brake linings and many under-the-hood automotive electrical components since the 1940s. Standard phenolics usually have wood flour filler. 

The recommended nominal criteria that can be employed in the design of the link are ultimate strength of NASA 2 Resin/143 cloth laminate at 300 K, 690 MPa stress concentration factor at pin, 2 and factor of safety, 3. These criteria, coupled with the loading parameters for the given application, determine the required cross-sectional area of the link. 

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