Styrene acrylonitrile failure

In a first full scale attempt at a new polymerisation process, the thermally unstable initiator was charged and heated to reaction temperature, but there was then an unforeseen delay of an horn before monomer addition was started. The rate of polymerisation effected by the depleted initiator was lower than the addition rate of the monomer, and the concentration of the latter reached a level at which an uncontrollable polymerisation set in which eventually led to pressure-failure of the vessel seals. Precautions to prevent such occurrences are detailed. In another incident, operator error led to catalyst, condensing styrene and acrylonitrile being ducted into an unstirred weighing tank instead of a reactor. When the error was recognised, the reacting mixture was dropped into drums containing inhibitor. One of the sealed drums had insufficient inhibitor to stop the reaction, and it slowly heated and eventually burst [1], The features and use of... 

Figure 3.23 Stress levels for cycles to failure for different plastics polycarbonate ( ), PP ( ), acrylonitrile-butadiene-styrene (ABS) (A), HDPE ( ) [32]...

Fig. 5.61 Dependence of failure stress of a variety of engineering polymers upon the number of cycles accumulated during a dynamic fatigue test at 2(fC. The polymers used were poly (methyl methacrylate) (PMMA), rigid poly (vinyl chloride) (PVC) and an acrylonitrile-butadiene-styrene copolymer (ABS). (After Bucknall, Gotham and Vincent Chapter 10 in Polymer Sciencey ed. Jenkinsy North-Holland, 1972.)...

Impact fatigue tests have also been conducted on some polymers namely Nylon 66, HIPS acrylonitrile butadiene styrene (ABS), and rubber-toughened Nylon. The impact energy was 98% of the crack initiation energy. Specimens withstood 100-200 cycles of loading before failure. 

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