<p>As DT 1769196, except that the flexibility and mouldability are improved by replacing the M-F precondensate by a polyethylene wax of density 0.91-0.92 and average m.w. 1500-7000. Composn. is thus 100 pbw finely divided wood, 25-900 pbw polyolefin and 5-30 wt. % wax.</p>