| 摘要 |
An instrument for determining polymer deflection temperatures, said instrument comprising a container holding an elongated sample of the polymer in a suspended position between its sample-supporting side walls, together with a plunger slidably engaged within said container and having a lower, wedge-shaped end which initially comes to rest against the undeflected sample in a position transverse to the longitudinal axis of the sample. A heater is employed to progressively elevate the temperature of the sample until the same deflects under the weight of the plunger, together with means associated with the plunger for signifying the resulting downward movement thereof and means for determining the temperature of the sample as this movement of the plunger occurs. In one embodiment, this downward movement of the plunger is detected by an electrobalance so arranged that a small suspended weight, spring-connected to the balance arm, is fully supported by the plunger as the latter rests against the nondeflected sample. This support is removed as the plunger moves downwardly with sample deflection, thereby causing a weight gain to be recorded by the electrobalance. The temperature of the sample at this point of weight gain is simultaneously read out from a thermocouple.
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