Resins thermoplastic properties

The chemistry of synthetic polymers is similar to the chemistry of small molecules with the same functional groups, but the physical properties of polymers are greatly affected by size. Polymers can be classified by physical property into four groups thermoplastics, fibers, elastomers, and thermosetting resins. The properties of each group can be accounted for by the structure, the degree of crystallinity, and the amount of cross-Jinking they contain. 

The polymerization of cyclic low-molar-mass polycarbonates, polyarylates, and PBT to high-molar-mass thermoplastics has been extensively studied by the General Electric Company during the last decade.57,58 Due to very low viscosity, cyclic oligoesters can be processed like thermosetting resins but retain thermoplastic properties in the final state, after polymerization in the presence of suitable... 

Thermoplastic processing, 10 178-179 of poly(ethylene oxide) resins, 10 684 Thermoplastic properties... 

A large diffusion may be found also for composite materials, carbon, or metal based. In the first case different types of polymeric resins (thermoplastics, such as polypropylene, polyethylene, and PVDF, or thermosettings, such as epoxies and phenolics) are filled with carbonaceous powders (graphite or carbon blacks), to provide a material characterized by very high chemical stability in the fuel cell environment and satisfactory properties of electrical conductivity, but which cannot offer sufficient robustness at thickness lower than 2 mm. The metal composite plates are essentially based on combinations (sandwiches of different layers) of stainless steel, porous graphite, and polycarbonates, with the aim to exploit the characteristics of different materials. Their fabrication can be more complex but this is compensated by the possibility to incorporate other functional components, such as manifolds, seals, and cooling layers. 

Importance of Hydroxyl Functionality. The hydroxyl content of each specific cellulose ester type is a very Important chemical variable. Relatively small changes may dramatically affect such properties as solubility or compatibility of the ester with other resins. Thermoplastic coatings formulated with cellulose esters with varying hydroxyl content exhibit varying degrees of compatibility with... 

Polyamides containing amino groups are also excellent flexibihzers for epoxies since they co-react with the epoxy resin and introduce their inherent thermoplastic properties. 

The crosslinking reaction, which occurs in the production of thermosets, also provides good adhesion to other materials. Therefore, epoxy and polyester resin matrices are used for fibre-reinforced composites, amino resins are used for bonding chipboard, while phenolics are used for bonding fibres in brake pads, and sand for metal casting. These specialised products do not fit in well with the discussion of thermoplastic properties in this... 

Vinyl Resins Thermoplastics polymer of vinyl compounds such as vinyl chloride or vinyl acetate. Have good weatherability, barrier properties, and flexibility, but deereased solvent and heat resistance. Processed by molding, extrusion, and eoating. Used in films and packaging. 

Thermoplastics are sometimes added to epoxy resins. Thermoplastic-modified epoxy resins [43,44] based on tri- and difunctional epoxy resins cured with DDS and blended with polyethersulfone form the basis for the matrix material in a composite used for the Boeing 777 aircraft. The incorporation of the thermoplastic helps the processing characteristics and also improves the mechanical properties, notably the toughness. The thermoplastic is able to phase separate from the epoxy phase and acts as a reinforcement for the epoxy matrix, enhancing its high temperature properties. The maximum use temperatures of all these resins will typically be 30 to 50 degrees lower than the cited Eg, assuming the same cure schedule. 

CAS 25377-73-5 EINECS/ELINCS 246-917-1 Uses Curing agent for epoxy resins corrosion inhibitor for nonaq. lubricating oils intermediate for prep, of alkyd or unsat. polyester resins, thermoplastics intermediate in chem. reactions also for drying oils, lacquers, paints, surfactants, asphalt additives, waterproofing agents, textiles, leather, starch modifier, germicides, hydrocarbon fuel additives Properties Lt. yel. clear vise, liq. m.w. 266 sp.gr. 1.003-1.008 vise. 440 cps b.p. 220 C (10 mm Hg) sapon. no. 418 neutral, no. 394-432 flash pt. 343-347 F... 

High-performance plastic (advanced plastic) n. Any neat, filled, or reinforced resin, thermoplastic or thermoset, that maintains stable dimensions and mechanical properties above 100°C. Some writers consider many of the engineering plastics to be high-performance plastics and the distinction is blurred. Others have limited the... 

Resins with long-chain macromolecules obtained by polycondensation have thermoplastic properties. Polyesters ( Terylene ) and polyamides (Nylon) are examples of polycondensations. The synthetic fibre Terylene (known as Dacron in the USA) is a polyester formed by the reaction of ethylene glycol with terephthalic acid the latter is obtained from p-xylene by oxidation ... 

On processing butadiene-styrene thermoplastic rubbers, the major effect on mechanical property deterioration is a result of the agglomeration of styrene particles [58]. For ABS (acrylonitrile-butadiene-styrene) resins, mechanical properties deteriorate on processing due to double bond oxidation. At more severe conditions, a decrease of the matrix resin [poly(styrene-co-acrylonitrile)] molecular weight is a superimposed effect [59]. 

Thermoplastic properties can be varied by mixing low- or high-density polyolefines, com starch and plasticizers. They all can be processed by typical plastics technologies, such as molding or film-blowing. Such resins contain up to 60-75% natural materials and up to 40% synthetic polymers. 

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