Temperature film casting

Thermal treatment and the nature of the casting solvent can also affect the deformation modes achieved in strained films of ionomers. For example, in films cast from polar dimethylformamide (DMF), the solvent interacts with ion-rich clusters and essentially destroys them, as is evident form absence of a second, higher temperature loss peak in such samples. As a result, even in a cast DMF sample of Na-SPS ionomer of high ion content (8.5 mol%), the only deformation mode observed in tensile straining is crazing. However, when these films are given an additional heat treatment (41 h at 210°C), shear... 

The block copolymer and the microsphere were cast from polymer-benzene solution on a Teflon sheet. The solution was gradually dried at room temperature. Film was microtomed vertically at 80 nm thick by the Ul-traCut-N (Reichert Nissei). In order to obtain enough contrast for TEM observation, the P4VP microdomains in the film were stained with OSO4. The film was observed by TEM (JEOL CX-100) at 100 kV. 

Contact angle measurements were obtained using a goniometer, measuring the advancing angle from 2 to 20 microliter drop sizes, of purified water upon polymer films at room temperature. Films were cast on metal plates and allowed to dry slowly from chloroform solutions. Several spots were measured on each film and the results averaged. 

Zirfon separator is a new alternative for Ni—H2 batteries. It is a porous composite separator material composed of a polysulfone matrix and ZrOz, which is present in a powder form. The manufacturing is based on the film-casting technique. It is very stable in concentrated KOH solutions at elevated temperatures. These films are around 300 /iin thick. SORAPEC has tested Zirfon in Ni—H2 cells and has indicated that it is one of the best separators. 

Figure 5. Shrinkage temperature profiles and membrane performances of Batch-513 films at two different temperatures of casting solutions...

Cowperthwaite, Coe, and Frissell (J) in their viscosity/temperature studies have defined the temperature at which the plastisol viscosity begins to increase as the gel temperature. These authors also studied the tensile strength of films cast on glass plates, fluxed at a series of temperatures between 300° and 425°F. They have defined the temperatures at which tensile strengths of 1000 and 1500 p.s.i. are attained as the fluxing temperatures. ... 

Figure 3. Glass transition temperatures for cast and pressed films of plasticized polycarbonate as a function of the weight fraction of plasticizer...

The mechanical properties and the tensile heat distortion temperatures (softening temperatures) of cast and pressed polycarbonate films containing differing amounts of plasticizer have been measured (Table III and IV). 

Incorporating small amounts of plasticizer during the manufacture of solvent-cast polycarbonate films results in films with a higher modulus of elasticity, a higher stiffness, and higher heat distortion temperatures than films cast from unplasticized polymer. 

Film. The blown film process is most commonly used in the production of PB film from resins with melt indexes from 0.3 io 10 g/10 min at a melt temperature of200-215DC using conventional equipment. Mechanical properties of blown PB film depend on the degree of orientation and other processing parameters. PB film can be sealed ai 100 220 (1. Another technique for the PB film production consists of film casting from the melt on polished chilled rolls and co-extrusion or lamination with other films. 

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