| 摘要 |
A polyurethane-quartz laminate suitable for aircraft radomes. Controlled amounts of a mixture of unpolymerized 4,4 diphenyl methane diisocyanate (MDI) and 2,4 toluene diisocyanate (TDI) are polymerized with ethylene glycol at a preselected temperatures and periods to produce a polymeric resin of relatively few nonpolar isocyanate groups. The resin is impregnated and cured in layers of quartz cloth to form a relatively high strength composite or laminate having a low dielectric constant.
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