| 摘要 |
<p>Mfr. of flexible PU foam without halocarbon blowing agent comprise reacting an MDI cpd. (I) with an active-H cpd. (II), at least 5 pts. wt. water per 100 pts. wt. (II) and opt. conventional additives, NCO index is 10-60 and at ratio (II) to water is less than 20, pref. 3-20. (II) is a polyether or polyester polyol or polyether polyamine of functionality 2-4 and equiv. wt. 750-5000. (I) may be MDI, MDI prepolymer, crude MDO opt. with some NCO gps. converted to carbodiimide, isocyanusate etc. NCO functionality is pref. 1.9-2.9, esp. 2-2.5. Functionality of (II) is pref. 2-3, equiv. wt. pref. 1000-2500.</p> |
