Alkali carbonate soln prodns -- it is contacted by carbon dioxide in the carbonator of a crossflow and alkali metal hydroxide

摘要

A thermally insulating structural laminate comprising a core of rigid plastic foam having two major surfaces, at least one of the major surfaces of the foam being attached to a facer comprising a fibrous sheet having at least one layer of an air-and moisture-impervious polymer disposed on the inner surface thereof and interposed between the fibrous sheet and the foam, the oxygen transmission of the polymer being a value of less than about 1 cc/100 in2-24 hrs-atm sufficient to make the facer substantially impervious to air and water vapor.