From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Hygroscopicity tests of various synthetic moulded materials.
| Identifier | ExFiles\Box 61\1\ scan0164 | |
| Date | 9th March 1931 | |
| COPY. WE.84. 9.3.31. TESTS FOR HYGROSCOPICITY OF VARIOUS SYNTHETIC MOULDED MATERIALS. Further to our report ref. WE.83 with reference to the various grades of bakelite insulating material, we have carried out hygroscopicity tests to determine the water absorption on a small sample of each grade. Each sample was carefully weighed in a dry state and then immersed in water at atmospheric temperature for 24 hours. After wiping dry the samples were again weighed and the percentage increase in weight noted. The following figures were obtained :- | Material | Weight dry. | Weight after immersion. | Percentage increase. | |---|---|---|---| | Poor -> Redmanol | 1.412 grms. | 1.722 grms. | 22% | | Stokes | 2.003 " | 2.028 " | 1.25% | | B.D.C. | 2.140 " | 2.158 " | .85% | | Best -> Nestorite F15. | 1.557 " | 1.567 " | .65% | | Nestorite F20. | 1.256 " | 1.271 " | 1.19% | EFC/HEW. | ||