Polyamide thermal properties

Polyamides can claim to have been the first engineering plastics as a result of their excellent combination of mechanical and thermal properties. Despite being iatroduced as long ago as the 1930s, these materials have retained their vitaUty and new appHcations, and iadeed new types of nylon continue to be developed. 

Fig. 6-14 specific modulus = modulus/density. Plastics include use of the heat-resistant TPs such as the polimides, polyamide-imide, and others. Table 6-21 provides data on the thermal properties of RPs. To date at least 80 wt % are glass fiber and about 60 wt% of those are polyester (TS) type RPs. 

Thermal properties. See also Temperature of aromatic polyamides, 19 718 of asbestos, 3 300-304 of diesel fuel, 12 423 of ethylene—tetrafluoroethylene copolymers, 18 319-321 of fibers, 11 167 of filled polymers, 11 309—310 of gallium, 12 342 of glass, 12 588... 

Although Tyrann-M/E and even conventional membranes are superior to the new polyamide and polyfvinylidene fluoride) membranes with respect to flow rates and filtration capacities, the latter two are more suitable for filtration of most (but not all) organic solvents and, partially as a result of their lower void volumes (Table IV) exhibit mechanical and thermal properties which are generally superior to those of the cellulosics. It should also be noted that in the special case of fiber-reinforced membranes, the mechanical properties are predominantly functions of the embedded fibers rather than of the membrane structu reverse. 

In situ polycondensation leads to aromatic polyamides or polyesters dispersed within the matrix of polyarylate. Mechanical and thermal properties of the films formed... 

This mixed product consists of small, platy particles with a relatively high surface area (15-20 m g ). The principal interest has to date been as a flame retardant Aller, principally for polypropylene. Both component phases decompose endothermically with the release of inert gas at relatively low temperatures. They are stable enough to allow incorporation into polymers such as polypropylene, but not polyamides. The performance of the two phases alone and in combination in polypropylene has been reported [91]. As expected from their thermal properties, hydromagnesite was the more effective flame retardant. The decomposition pathway of hydromagnesite has been shown to be considerably affected by pressure and this may affect its flame retardancy [71]. 

High-performance ahybrid resins were prepared by Yamada et al. (1) having excellent heat resistance and thermal properties. These consisted of hyper-branched polyamide resins derived from the pyromellitic dianhydride with triamines such as 1,3,5-triamino benzene that were postreacted with... 

PEBA exhibit a two-phase (crystalline and amorphous) structure and can be classified as a flexible nylon. Physical, chemical, and thermal properties can be modified by appropriate combination of different amounts of polyamide and polyether blocks [149], Hydrophilic PEBAs can be prepared which can have specific applications in medical devices. Similarly to other thermoplastic elastomers, the poiyamide-based ones find applications in automotive components, sporting goods conveyor belting, adhesives, and coatings [150]. In recent years the world consumption was approximately 6400 tons per year with about 80% in Western Europe and the rest equally split between the United States and Japan [143],... 

It was in 1976 that Ogata et al. reported the synthesis of inclusion polyamides [78]. When /1-cyclodextrin was stirred with aliphatic diamines in water, precipitates were formed and they were characterized as inclusion compounds. Condensation of these inclusion amides with isophthaloyl or terephthaloyl chloride yielded polyamides encircled by many of the cy-clodextrins, i.e., the first pseudopolyrotaxanes. Ogata et al. likened them to a train passing through many tunnels . The solubility and water absorption of the pseudorotaxanes were greater than those of the naked polymer threads. Differential thermal analysis experiments showed that the thermal properties of the pseudorotaxanes were different both from the naked threads and from /1-cyclodextrin. 

Barikani, M., and S. Mehdipour. 1999. Synthesis, characterization and thermal properties of novel arglene sulfure ether polyinides and polyamides. Journal of Polymer... 

Thermal Properties. Some wholly N-methylated aromatic polyamides have been reported previously and found to be considerably lower in thermal stability than the corresponding unsubstituted polymers. Thus, Koton reported that the softening point of VII was 247°C, a temperature much below that of PPD-T, which shows no softening point below 400°C. 

Table 4. Thermal properties and solubility of polyamide 15 with or without aromatic substituent...

Polyimide and polyamide-imide Excellent thermal properties Good composite properties Good electrical properties Good fire properties Restricted choice of color Arc resistance Acid and alkali resistance... 

Long fiber reinforced compounds polyamides. Basic/mechanical/thermal properties ... 

Lopez-Carrasquero. F. Monserrat. S. Martinez de Har-duya, A. Munoz-Guerra, S. Stmcture and thermal properties of new comblike polyamides. Macromolecules 1995. 28. 5535. 

Save energy processing at low temperatures of injection moulding (<160 °C), mechanical properties similar to those of polyamide, thermally stable at least till 95 °C or even 105 °C. 

An example of a typical material composition is the combination of a polymer and a filler. Because compounding is a techiuque that can complement the drawbacks of conventional polymers, it has been studied over a long period and its practical apphcations are well known. Reinforcing materials such as short-fiber are often used for compounding with thermoplastic polymers in order to improve their mechaiucal or thermal properties. Polypropylene and polyamide (nylon) are used for the thermoplastic polymers, while glass fiber and carbon fiber are mainly used as reinforcing materials. A few ttm... 

MECHANICAL AND THERMAL PROPERTIES OF AN AROMATIC POLYAMIDE YARN /HT-1 OR NOMEX/. 

Caamano, C., Grady, B., Resasco, D.E. (2012) Influence of nanombe characteristics on electrical and thermal properties of MWCNT/polyamide 6,6 composites prepared by melt mixing. Carbon, 50, 3694—3707. 

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