摘要 |
<p>A curable aqueous binder has two primary components. The first component is a bio-based material or mixture of bio-based materials such as starch or polyvinyl alcohol. The second component is one or more compounds selected from the group of urea, polyurea and substituted urea. The first and second components make up most (i.e. 50% or more) of all solids in the binder. The dry weight of the second component is preferably 25% or more of the dry weight of the first component. The solids content of the binder is preferably between 6 wt% and 20 wt%. A method of making a mineral fiber product includes a step of curing a binder as described above in situ on a mass of mineral fibers at a temperature of 175 degrees C or more. A preferred binder is a mixture of urea and starch in a ratio by weight between 50-50 and 80-20 in water at a solids content of 10-20 wt%, substantially without other components, and may be used as a replacement for formaldehyde or petrochemical based resins. The starch is preferably cooked, thermoplastic or nanoparticle starch.</p> |