Polyphenylene oxide tensile strength

When the temperature rises, polyphenylene sulfide can be attacked by hot strong acids and bases, chlorinated solvents, oxidizing agents, halogens, amines. For example, a given grade is unusable after a few months in 10% nitric acid at 90°C. After 1 year at 90°C in 37% hydrochloric acid, the retention of tensile strength is 29%. 

Various adhesives can be used to bond polyphenylene oxide to itself or to other substrates. Parts must be prepared by sanding or by chromic acid etching at elevated temperature. Methyl alcohol is a suitable solvent for surface cleaning. The prime adhesive candidates are epoxies, modified epoxies, nitrile phenolics, and polyurethanes. Epoxy adhesive will provide tensile shear strength on abraded polyphenylene oxide substrates of 600 to 1300 psi and 1300 to 2200 psi on etched (chromic acid) substrates.71... 

Results of some of these short-term tests are shown in Table II. A comparison is given between PPS and five other plastics nylon (Zytel 101), polycarbonate (Lexan 141), polysulfone (Bakelite Polysulfone), polyphenylene oxide (Noryl), and polyetherimide (Ultem 2300). The data presented are based upon retention of tensile strength for all plastics except the Ultem 2300, which is based upon retention of flexural strength. Unsuccessful attempts were made to injection mold ASTM Type IV tensile bars out of the Ultem compound, but flexural strength bars could be made. Experience has shown that chemical resistance tests monitored by flexural strength retention are comparable to those monitored by retention of tensile strength. 

The incorporation of 30% of glass fiber into polyphenylene oxide brings about a relatively small increase in tensile strength from between 50 and 65 MPa for the unreinforced polymer to 85 MPa in the reinforced polymer (Table 3.1). The addition of glass fiber is accompanied by an increase in flexural modulus from 2.5 to 17.2 GPa (Table 3.2) and a dramatic decrease in modulus of elasticity from between 20 and 60% down to 1% (Table 3.4). The incorporation of glass fibers into polyphenylene oxide produces a distinct improvement in the wear resistance of the reinforced polymer accompanied by small improvements in fatigue index [19] and the coefficient of friction [20]. 

Figure 4 shows an example of a nylon-alloy. In order to improve the impact-strength of nylon, we used to blend rubber with nylon, but the blend of rubber resulted in the reduction of tensile-modulus and heat-stability. We then, improve tensile-modulus and heat-stability by meansof blending the nylon-alloy with polyphenylene oxide, which possesses a higher glass transition temperature. When rubber and polyphenylene oxide are blended separately or independently in nylon, we could not obtain the desired properties. But when the micro-structure of the blend is controlled, as polyphenylene oxide is first blended in nylon and the rubber is finely dispersed in the polyphenylene oxide phase, a heat-stable, high impact-strength nylon is obtained. 

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