| 摘要 |
<p>A moulding composition which forms stable, durable mouldings which are colour stable, have good water resistance and can be glass clear and fire-resistant, comprises a melamine-formaldehyde resole of mole ratio melamine:formaldehyde in the range 1:1.1 to 1:5.0, and from 20 to 80% by weight, based on the resole, of a glycol or glycol derivative. The composition may also contain one or more of water, polyvinyl alcohol, aluminium hydroxide and reinforcing fillers. The melamine in the resole may be partially replaced with urea. Cure of the resin composition, after shaping, takes place at a pH of a least 6.0, and is accelerated by boron oxide and also by microwave heating. Foamed products are especially useful.</p> |
