| 摘要 |
Compsns. (I) are made by reacting (A) addn. prod., contg. 1-24% (all pts. wt.) NCO gps., obtd. by reacting a di- or poly-isocyanate with OH-contg. polyether (II) comprising more than 40% ethylene oxide (units), ratio of NCO:OH gps. being more than 1 (B) aq. dispersion of olefinically unsatd. cpds. polyurethanes, or bitumen emulsion, and opt. (C) water and/or (D) accelerator or retarder for reaction of (A), (B), and (C), and/or (E) inert diluent for (A) which is miscible with (B), (C), and (D), and/or (F) free di- or poly-isocyanate as additive for (A). (I) are used by (1) adding components in one lot and injecting, or (2) mixing (B) (opt. as mixt. with (C) and (D)) with (A), opt. mixing with (E), opt. adding (D) and (F), and combining with vigrous mixing then injecting. USE/ADVANTAGE - Caulking pores, capillaries, joints, cracks, and crevices in building materials and parts, canal systems, and geological structures. Hardened (I) have good mechanical strength and high elasticity and can be used to seal off flowing water under pressure such as water break-ins during tunnel construction.
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