| 摘要 |
<p>The present invention is an impact resistant composite and helmet made thereof. The helmet comprises an impact resistant composite shell. The composite shell comprises a plurality of prepreg packets. Each prepreg packet comprises at least about 2 and preferably 5 to 20 prepreg layers. There are from 2 to 50 and preferably 5 to 20 prepreg packets. Each prepreg layer comprises a plurality of unidirectional coplanar fibers embedded in a polymeric matrix. The fibers of adjacent layers in the prepreg packets are at an angle of from 45 DEG to 90 DEG , preferably 60 DEG to 90 DEG , more preferably 80 DEG to 90 DEG and most preferabaly about 90 DEG from each other. The angle of the fiber in alternate layers is preferably, sustantially the same.</p> |
