Thermoplastic polyester polymers

Features Thermoplastic polyester polymer Properties Clear It. amber pellet disp. in water, cyclohexanone, dimethyl sulfoxide, diethylene glycol m.w. 10,000 melt vise. 9700 poise (200 C) soften, pt. 38 C acid no. < 2 hyd. no. < 10 anionic 100% solids Eastman AQ55S [Eastman]... 

Features Thermoplastic polyester polymer high humidity hold in hair sprays... 

Thermoplastic polyester polymers are used extensively in the production of film and fibers. They are high crystalUne, with a melting point of over 204 C. They are fairly translucent in thin molded sections and opaque in thick sections but can be extruded into transparent thin film. Both reinforced and unreinforced formulations are extremely easy to process and can be molded in very fast cycles. 

Polyethylene terephthalate (PET) is a polymer that has been extensively used in cardiovascular implements and patches for multiple decades, ever since its introduction in England in 1939, followed by the development of its fiber form by DuPont in 1950. Sold in the United States under the brand name Dacron, PET is a thermoplastic polyester polymer resin used in the textile industry in the design of synthetic fabrics [9]. PET is composed of alternating chains of glycol and terephthalic acid. 

Features Thermoplastic polyester polymer high humidity hold in hair sprays Regulatory DOT nonregulated SARA 313 nonreportable Canada WHMIS non-controlled Canada DSL Europe EINECS Australia AlCS Japan MITI Korea ECL... 

Global consumption of thermoplastic mbbers of all types is estimated at about 600,000 t/yr (51). Of this, 42% was estimated to be consumed in the United States, 39% in Western Europe, and 19% in Japan. At present, the woddwide market is estimated to be divided as follows styrenic block copolymers, 48% hard polymer/elastomer combinations, 26% thermoplastic polyurethanes, 12% thermoplastic polyesters, 4% and others, 9%. The three largest end uses were transportation, 23% footwear, 18% and adhesives, coatings, etc, 16%. The ranges of the hardness values, prices, and specific gravities of commercially available materials are given in Table 4. 

In Chapters 3 and 11 reference was made to thermoplastic elastomers of the triblock type. The most well known consist of a block of butadiene units joined at each end to a block of styrene units. At room temperature the styrene blocks congregate into glassy domains which act effectively to link the butadiene segments into a rubbery network. Above the Tg of the polystyrene these domains disappear and the polymer begins to flow like a thermoplastic. Because of the relatively low Tg of the short polystyrene blocks such rubbers have very limited heat resistance. Whilst in principle it may be possible to use end-blocks with a higher Tg an alternative approach is to use a block copolymer in which one of the blocks is capable of crystallisation and with a well above room temperature. Using what may be considered to be an extension of the chemical technology of poly(ethylene terephthalate) this approach has led to the availability of thermoplastic polyester elastomers (Hytrel—Du Pont Amitel—Akzo). 

Polymer-matrix materials include a wide range of specific materials. Perhaps the most commonly used polymer is epoxy. Other polymers include vinyl ester and polyester. Polymers can be either of the thermoset type, where cross-linking of polymer chains is irreversible, or of the thermoplastic type, where cross-linking does not take place but the matrix only hardens and can be softened and hardened repeatedly. For example, thermoplastics can be heated and reheated, as is essential to any injection-molding process. In contrast, thermosets do not melt upon reheating, so they cannot be injection molded. Polyimides have a higher temperature limit than epoxies (650°F versus 250°F or 350°F) (343°C versus 121°C or 177°C), but are much more brittle and considerably harder to process. 

Polyesters are one of the most versatile classes of polymers ever produced, covering a wide range of properties and applications. Polyesters are present in fibers, engineering thermoplastics, and high-performance polymers as well as in thermosetting resins and elastomers. Table 2.1 lists the chemical structure, abbreviations, and uses of some commercially important thermoplastic polyesters. 

Thermoplastic molding applications for VDC copolymers, 25 726-727 Thermoplastic olefin polymer of amorphous structure (TOPAS), 16 113 Thermoplastic polyester bottles, recycling, 20 54-56... 

Thermoplastic polyesters, 20 31-95. See also Liquid-crystal polymers (LCPs) blow-molded bottles, 20 45-47 bottles for demanding contents, 20 52-53... 

Cheong, S. I. and Choi, K. Y., Modeling of a continuous rotating disk polycondensation reactor for the synthesis of thermoplastic polyesters,. /. Appl. Polym. Sci., 61, 763-773 (1996). 

The primary crystalline polymer based on CHDM is the terephthalate, poly(1,4-cyclohexylenedimethylene terephthalate) (PCT). This polyester was originally developed for fiber applications but has since found wider utility as a reinforced polymer for injection molding and (when copolymerized with a small amount of isophthalic acid) as a material for crystallized food packaging trays. The key property of PCT which sets it apart from other thermoplastic polyesters in these latter applications is its melting point. 

Solid-state polycondensation (SSP) is thus a technique applied to thermoplastic polyesters to raise their molecular weight or IV. During solid-state polycondensation, the polymer is heated above the glass transition temperature and below the melt temperature of the polymer either under an inert gas or under vacuum. Increasing the intrinsic viscosity requires a residence time of up to 12 h under vacuum or under inert gas, at temperatures from 180 to 240 °C. 

Eigure 6 shows the stiffness of Ecoflex /PLA blends depending on the PLA amount. PLA today is a thermoplastic polymer made from renewable raw materials and is available on industrial scale. Blending the completely different thermoplastic polyesters - stiff and brittle PLA with soft and flexible Ecoflex - a whole range of different material properties can be accessed, depending on the ratio of both polymers. 

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