| 摘要 |
<p>A process for preparing a rigid modified polyisocyanurate foam composition, which comprises reacting a methylene diisocyanate with a polyalkylene glycol composition comprising a C1-C3 alkoxy poly C1-C3 alkylene glycol, the reaction being carried out in the presence of a blowing agent, a surfactant and a trimerisation catalyst. - (9pp) EPAB- EP-116068 B A process for preparing a rigid modified polyisocyanurate foam composition, which comprises reacting a methylene diisocyanate with a polyalkylene glycol composition comprising a C1-C3 alkoxy poly C1-C3 alkylene glycol, the reaction being carried out in the presence of a blowing agent, a surfactant and a trimerisation catalyst. USAB- US4426461 A Modified foam compsns. having good fire resistance are prepd. by reacting 100 pts.wt. methylene diisocyanates, functionality esp. below 2.7 (more esp. below 2.4), with 5-40 pts.wt. 1-3C alkoxypoly 1-3C alkylene glycols (I), HO no. esp. max. 150, in presence of a blowing agent, a surfactant and a single-stage, rapid, high-exotherm trimerisation catalyst, esp. K octoate, a quat. ammonium cpd. (more esp. N-hydroxyalkyl quat. ammonium carboxylic salts). Esp. (I) is (A) 5-20 pts. methoxypolyethylene glycol, HO no.max. 100 (more esp. CH3O(CH2CH2O)nH where n is 2-20 and mol. wt. is below 600); or (B) polyethyleneglycol methoxy polyethyleneglycol mixts.; and temp. rises to 230 deg.F within 10 seconds of mixing. Opt. melamine is included as flame retardant, esp. in amts. in excess of (I). - Foams have low flame spread and smoke properties with high char resistance; compressive strength is high, K-value low and they are appropriate for applications in the construction and insulation industry. (0/0)</p> |
