Phenolic Laminates Research Articles

Thermal degradation of resins

AbstractDifferential thermal analysis and thermogravimetric analysis techniques were investigated with a view to predication of the thermal behavior and flammability of plastics materials. Paper‐reinforced phenolic and epoxide resins were used. It was found that with phenolic laminates the pattern of the thermograms was characteristic of the paper, while with epoxide laminates (and melamine) it was characteristic of the resin used. This cannot be correlated with fireproofness or flammability, and further work is necessary to establish better techniques and to study the thermal behavior of the laminates by service testing.

フェノールレジン積層板のせん断加工 (第5報)

フェノールレジン積層板のせん断加工 (第5報)

フェノール樹脂積層板の回転曲げ疲労試験

A rotating bending fatigue test was conducted for the phenolic resin laminates. The purpose of this test was to investigate the effect of the difference of base cloth and of cut out direction of test piece (parallel to the warp or woof of the cloth) on the fatigue strength.In the fatigue test of high polymer material, it is generally known that specimens produce a considerable heat. The problem of this heat producing has not been analyzed, because of the difficulties in measuring the temperature of rotating beam specimen. Therefore, we coated thermopaint on the surface of the specimens in all the fatigue tests so that the temperature might be measured, and obtained, for the high polymer materials, S-N curves different from those for metallic materials.Main test results obtained are as follows: Rotating bending fatigue limits of phenolic resin laminates show no great difference among laminates of various cotton cloth. The fatigue limit of fiberglass cloth laminate is about twice as high as the former. Between the specimens cut out from the laminate parallel to the warp and woof of the cloths, it is difficult to determine which is more endurable.The S-N curve of cotton cloth laminates consists of two curves for the smaller and larger total numbers of revolution. This is due to the internal heat producing phenomenon of specimen. The effect of internal heating on the fatigue strength is remarkable for the smaller total number of revolution (N<105-106), and is not for the larger one (N>105-106). Accordingly, at a fatigue endurance limit (N=107), its effect seems to be negligible.

フェノールレジン積層板のせん断加工

フェノールレジン積層板のせん断加工

Measurement of Triboelectric Response of Raw Cottons

By use of a novel commutator method, triboelectric potentials produced by rubbing cotton with various materials have been measured by comparison with known D.C. potentials. Results are given here for fiberboard (phenolic resin laminate, fabric base), cork roller material, syn thetic rubber roller material, Lucite, polystyrene, glass, and cellulose acetate sheet, used as rubbing materials on three varieties of cotton and trash extracted from baled cotton. The purpose of this study was to learn if the sufficiently great differences in triboelectricity produced by cot tons and trash could be used practically in the electrostatic cleaning of cotton.

The Effect of "After Curing" of Phenolic Laminates

The Effect of "After Curing" of Phenolic Laminates

Chemical Resistance of Phenolic Laminates

Abstract Eight representative types of phenolic laminates were immersed in various aqueous chemical solutions for 6 months and tested periodically for weight change, dimensional change, and strength losses. On the whole, any laminate which has the desired properties after prolonged immersion in water alone would also be satisfactory for other field conditions, with the exception of a strong acid condition or any alkaline condition. Where alkaline or strong acid conditions are involved, special care must be taken in the selection of laminates to be used.