Solubility thermoplastic polymers

Poly(ethylene oxide) [25322-68-3] (PEO) is a water-soluble, thermoplastic polymer produced by the heterogeneous polymerization of ethylene oxide. The white, free-flowing resins are characterized by the following stmctural formula ... 

Soluble thermoplastic polymer additions (e.g., epoxy-nylon and epoxy-vinyl) provide very tough and somewhat flexible systems, but they are limited because of their high viscosity and high raw materials costs. Almost all these systems need to be handled at elevated temperatures or as solvent solutions. They require elevated temperature to achieve wetting and cure. 

The use of well characterized polymers with controlled silicon to carboir, nitrogen, oxygen or other heteroatom ratio first reported by Yajima [21] is now emerging as a flexible and important route to silicon carbide, silicon nitride, silicon oxide and other silicon-based inorganic materials and structures. Typically a soluble thermoplastic, polymer with the correct silicon to heteroatom ratio is extruded or coated in the desired shape or form, then converted to a ceramic by heating. 

Properties. Hydroxypropylcellulose [9004-64-2] (HPC) is a thermoplastic, nonionic cellulose ether that is soluble in water and in many organic solvents. HPC combines organic solvent solubiUty, thermoplasticity, and surface activity with the aqueous thickening and stabilising properties characteristic of other water-soluble ceUulosic polymers described herein. Like the methylceUuloses, HPC exhibits a low critical solution temperature in water. 

Resultant multiphase copolymers displayed properties ranging from soluble thermoplastic elastomers and engineering polymers to intractable thermosets, depending on the backbone composition and orientation, and especially the level of ODA incorpora-... 

Solvent extraction of the polymer from shredder residue is only suitable for soluble thermoplastics. 

These highly amorphous elastomers have relatively low Tt values (—73 C) and tend to crystallize when stretched. The cold flow of these thermoplastic polymers is reduced when they are crosslinked (vulcanized) with a small amount (2%) of sulfur. Since these polymers of isoprene have a solubility parameter of 8.0 H, they are resistant to polar solvents but are soluble in many aliphatic and aromatic hydrocarbon solvents. The cross-linked derivatives swell but do not dissolve in these solvents. 

Inulin etherification products have utility in cosmetics or pharmaceuticals as carriers for water-insoluble substances or to stabilize aqueous solutions of compounds with low water solubility. They may also be used as emulsifiers or as an additive in textiles and paper and as softeners of thermoplastic polymers (Kunz and Begli, 1995). 

Johnson et al. (15) reported the first attempt to synthesize PEEK by polycondensation of bisphenolate with activated dihalides using DMSO as a solvent and NaOH as a base. High molecular weight polymers were difficult to obtain due to the crystallinity and the resulting insolubility of polymers in DMSO. To circumvent the solubility problem, Attwood and Rose (16) used diphenyl sulfone as a solvent, and the polymerization was carried out close to the melting point. Victrex PEEK was commercialized by the British company ICI in 1982 using this method. Since its commercialization, this thermoplastic polymer has been used in a wide range of applications, from medicine to the electronic, telecommunications and transport industries (automobile, aeronautic and aerospace) (17,18). 

The first reported (8) siloxane-polyimide polymer was synthesized from l,3-bis(aminopropyl)-l,l,3,3-tetramethyldisiloxane and pyromellitic dianhydride. This material was described as a soluble, thermoplastic polyimide. Many other siloxane-polyimide polymers have been prepared via similar methodology using other dianhydrides and diamines (9). 

In contrast to the linear thermoplastic polymers, which are soluble and fusible, the cross-linked network polymers are insoluble and infusible. They are formed from polymerizing systems containing monomers or prepolymers with a functionality of three or more. A good example is the phenol-formaldehyde resin systems. The cross-linking reaction takes place in the bond under applied pressure and heat, and the whole adhesive bond might consist of only one super giant molecule. Such resins are, therefore, called thermosetting resins. 

Polyco [Borden], TM for a series of thermoplastic polymers in the form of water emulsions or solvent solutions, applied to vinyl acetate polymers and copolymers, butadiene-styrene copolymer lat-ics, polystyrenes, vinyl and vinylidene chloride copolymers, acrylic copolymers, and water-soluble polyacrylates. 

When block copolymerization was done, isoprene, styrene, or butadiene was prepolymerized at room temperature, and cyanoprene polymerized at low temperatures. Styrene gave thermoplastic polymers butadiene, depending on the quantity ratio selected, gave thermoplastic to rubberlike polymer soluble in polar solvents such as DMF, but largely resistent to organic solvent such as toluene. 

The chart shown in Figure 41 -6, p. 487, by H. Clotier and J.E. Prud homme can be used to identify 29 thermoplastic polymers based on solubility and is the basis for Experiment No. 57. 

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