Nonrigid polymers

In nonrigid ionomers, such as elastomers in which the Tg is situated below ambient temperature, even greater changes can be produced in tensile properties by increase of ion content. As one example, it has been found that in K-salts of a block copolymer, based on butyl acrylate and sulfonated polystyrene, both the tensile strength and the toughness show a dramatic increase as the ion content is raised to about 6 mol% [10]. Also, in Zn-salts of a butyl acrylate/acrylic acid polymer, the tensile strength as a function of the acrylic acid content was observed to rise from a low value of about 3 MPa for the acid copolymer to a maximum value of about 15 MPa for the ionomer having acrylic acid content of 5 wt% [II]. Other examples of the influence of ion content on mechanical properties of ionomers are cited in a recent review article [7],... 

The key question is "How does one establish film rigidity " One approach involves analysis of the shape, as well as position, of the resonance. Essentially, one determines the Q-factor for the crystal broadening signals nonrigidity. It is important to appreciate that immersion of the crystal in the liquid significantly broadens the resonance. Small changes in Q-factor associated with incomplete polymer film rigidity may therefore be difficult to detect, and certainly complex to quantify. 

Aspects of loading with nonrigid films have been considered by several authors [18-22]. The primary case of interest in the electrochemical context is loading with a rigid layer (the elechode), a viscoelastic film (commonly, though not necessarily, a polymer), and then a Newtonian fluid, schematically illustrated in Fig. 3. (The rigid layer component may also include material entrapped within sm-face features [23].) The characteristic mechanical impedances of the two nonrigid... 

ASTM D2287-96(2001) Standard Specification for Nonrigid Vinyl Chloride Polymer and Copolymer Molding and Extrusion Compounds... 

Standard Test Method for Copper Strip Corrosion by Industrial Aromatic Hydrocarbons Standard Test Methods for Nonrigid Vinyl Chloride Polymer Tubing Used for Electrical Insulation Standard Practice for Substitute Ocean Water Standard Specification for Reagent Water... 

D876 Nonrigid vinyl chloride polymer tubing D729 Vinylidene chloride molding... 

Supported bilayer A lipid or other surfactant bilayer deposited on a nonrigid substrate such as a polymer network. 

D2287 Nonrigid Vinyl Choloride Polymer and Copolymer... 

Fig. 32. Loss index at different temperatures as a function of frequency, (a) Glassy polymer with nonrigid side groups, (b) Crystalline polar polymer with partially locked dipoles.

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