摘要:
Thermoplastic polyurethanes (TPU) based on NDI are prepared by reacting specific, storage-stable NDI-based NCO prepolymers with chain extenders and granulating the largely reacted and cooled reaction melt. The TPU granules can then be processed to form shaped articles.
摘要:
Stable NCO prepolymers are produced from polyisocyanates having a melting point greater than 70° C., preferably, naphthalene diisocyanate, having advantageous physical properties. An important feature of the process of the present invention is the rapid cooling of the prepolymer. The process of the present invention may be carried out on a continuous or batch basis. The prepolymers of the present invention are particularly suitable for the production of cast polyurethane elastomers.
摘要:
Stable NCO prepolymers are produced from polyisocyanates having a melting point greater than 70° C., preferably, naphthalene diisocyanate, having advantageous physical properties. An important feature of the process of the present invention is the rapid cooling of the prepolymer. The process of the present invention may be carried out on a continuous or batch basis. The prepolymers of the present invention are particularly suitable for the production of cast polyurethane elastomers.