Physical and Chemical Properties | Chemical properties Strong adhesion, good flexibility, good acid and alkali resistance, good comprehensive performance. |
Use | Applications for light-curing coatings and printed circuit boards, adhesives, inks, etc. |
Polyurethane-type photosensitive prepolymer is obtained by reacting polyisocyanate with double or polyhydroxy compounds with different structures and molecular weights to form terminal isocyanate intermediate compounds, and then reacting with β-hydroxyalkyl acrylate. In order to obtain resins with different properties, people have studied prepolymers with different structures:
Synthesis of polyurethane photosensitive prepolymer whose soft segment is glycol (including polyether glycol);
The soft segment is the synthesis of unsaturated polyester type polyurethane photosensitive prepolymer;
Polyurethane prepolymer with polysiloxane as soft segment;
A polyurethane prepolymer that can form an interpenetrating network.
Polyurethane prepolymer adopts solution polymerization method: the solution synthesis of polyurethane prepolymer is generally divided into two steps. First, the polyisocyanate, an appropriate amount of catalyst and tetrahydrofuran are mixed in a four-port bottle. Under the protection of nitrogen, the temperature does not exceed 85 ℃ and the HPA is reacted for 4 hours to obtain the para-adduct; then a certain amount of catalyst, The dihydroxy or polyhydroxy compound of the polymerization inhibitor is added dropwise to the above adduct, and the reaction is at 85 ℃ for 6 hours to obtain.