Inert polymer

Hydroxy-terminated polyester (HTPS) is made from diethylene glycol and adipic acid, and hydroxy-terminated polyether (HTPE) is made from propylene glycol. Hydroxy-terminated polyacetylene (HTPA) is synthesized from butynediol and paraformaldehyde and is characterized by acetylenic triple bonds. The terminal OH groups of these polymers are cured with isophorone diisocyanate. Table 4.3 shows the chemical properties of typical polymers and prepolymers used in composite propellants and explosives.All of these polymers are inert, but, with the exception of HTPB, contain relatively high oxygen contents in their molecular structures. 

carboxy-terminated polybutadiene, CTPB (1) imine-type curative 

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Solid solutions of transport-active molecules in an inert polymer... 

Slides Covering pipelines with polymeric films cathodic protection of pipelines, ships, etc.. With zinc bracelets use of inert polymers in chemical plant galvanic corrosion in architecture (e.g. A1 window frames held with Cu bolts) weld decay. 

Sample bag A. bag made from an inert polymer such as Teflon, complete with a fitting for connecting to an air-sampling pump. 

N.S. Cohen et al, A1AA J 12 (2), 212-18 ( qia QQt 135471 (1974V The effects of inert polymer binder properties on composite solid proplnt burning rate are described. Surface pyrolysis data for many polymers over a wide range of conditions are used to derive kinetics constants from Arrhenius plots and heat of... 

EB irradiation (like the other ionizing radiation techniques) can bring about the vulcanization of saturated chemically inert polymers which cannot be achieved in the conventional thermochemical curing methods [44]. 

Inert Polymers, with Excellent Mechanical Properties, and Low Surface Energy Suitable for Implantation Purposes ... 

This result demonstrates that the self-spreading dynamics are controllable by tuning the bilayer-substrate interactions. The above-mentioned electrolyte dependence is an example of this fact. Considering that there are many parameters that alter the bilayer-substrate interaction, a diverse approach can be proposed. For example, Nissen et al. investigated the spreading dynamics on the substrate coated with polymetic materials [48]. They found that insertion of a hydrophilic and inert polymer layer under the self-spreading lipid bilayer strongly attenuated the bilayer-substrate interaction. 

During the last few years, new developments in polymer photochemistry have made it possible to graft various functional monomers onto surfaces of inert polymers like polyethylene, polypropylene and polyethyleneterephthalate. In the first attempts, initiator and monomer were transferred in vapor phase into a "UV Cure" irradiator containing the polymer sheet to be surface grafted. 

Inert polymer matrices, studied for use in possible controlled release applications, have used porosimetry to investigate a number of properties [54-56]. The kinetics of liquid capillary penetration into these matrices was explored using a modified Washburn equation [54]. It was shown that water... 

The first CEM system described by Griffing and West (84) consisted of an organic dye dispersed in an inert polymer film that is spin coated onto the surface of a resist and subsequently removed following exposure but prior to resist development. The chemistry of this system is based on the photoisomerization of an aromatic dye to an oxaziridine (87) (Figure 10). Other workers have evaluated polysilanes (88) and diazonium salt chemistry (89,90) for CEM applications. 

Structure-activity studies are probably adequate for some substances. An example would be inert polymers whose monomeric components have been well-characterized toxicologically. For other chemicals, analyses based on a review of structural analogues may prove inadequate for at least three reasons. 

Solubility/miscibility Soluble in both hot and cold water Biological considerations Practically inert polymer... 

Inert system By a combination of the use of inert materials (glass, titanium, and inert polymers) this system offers totally inert fluidics. Primary features of the system include (Fig. 1.2 (d)) ... 

Polypropylene (PP) is a hydrophobic and chemically inert polymer which needs to be activated in order to be functional as a support for NA immobilization. Typically, PP membranes are aminated by exposure to an ammonia plasma generated by radiofrequency plasma discharge. Once aminated, the PP membranes can be reacted with derivatized ONDs using common coupling methods [56-58]. 

Typical crystalline materials used as oxidizers are perchlorates, nitrates, nitro compounds, nitramines, and metal azides. The polymeric materials used as fuel components are divided into nitrate esters, inert polymers, and azide polymers. Optimized combinations of these oxidizer and fuel components yield the desired ballistic characteristics of propellants or explosives. 

Three types of polymeric materials are used inert polymers, active polymers, and azide polymers. No exothermic heat is produced when inert polymers are decomposed thermally. On the other hand, exothermic reactions occur when active polymers and azide polymers are decomposed. Self-sustaining burning is possible when active polymers and azide polymers are ignited. 

Inert polymers are classified according to their chemical bond structures. Figure 4.4 shows typical basic polymer units and bond structures.Pil These polymers are based on hydrocarbon structures that have relatively low viscosities during... 

Polymeric materials used as fuel components of pyrolants are classified into two types active polymers and inert polymers. Typical active polymers are nitropoly-mers, composed of nitrate esters containing hydrocarbon and oxidizer structures, and azide polymers, containing azide chemical bonds. Hydrocarbon polymers such as polybutadiene and polyurethane are inert polymers. When both active and inert polymers are mixed with crystalline oxidizers, polymeric pyrolants are formed. 

For many processes, how ever, it is necessary to employ a divided cell in which the anode and cathode compartments are separated by a barrier, allowing the diffusion of ions but hindering transfer of reactants and products between compartments. This prevents undesirable side reactions. Good examples of the need for a divided cell are seen in the reduction of nitjobenzenes to phenylhydroxylamines (p. 379) or to anilines (p. 376). In these ca.scs the reduction products are susceptible to oxidation and must be prevented from approaching the anode. The cell compartments can be divided with a porous separator constructed from sintered glass, porous porcelain or a sintered inert polymer such as polypropene or polytetra-... 

Little was done with this new material until the military, working on the atomic bomb, needed a special material for gaskets that would resist the corrosive gas uranium hexafluoride, which was one of the materials used to make the atomic bomb. General Leslie Groves, responsible for the U.S. Army s part in the atomic bomb project, had learned of DuPont s new inert polymer and had DuPont manufacture it for them. 

Aerosols generated by nebulization are directed through a spray chamber, which is usually constructed from glass, or an inert polymer (Fig. 4.9) The spray chamber prevents larger aerosol droplets from reaching the plasma, as... 

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