Aliphatische Harze auf Petroleumbasis, Verfahren zur Kontrolle von deren Erweichungspunkt und deren Molekulargewicht, und druckempfindliche Schmelzklebstoffe, die diese enthalten.

摘要

The invention provides a petroleum-based aliphatic resin having a) a Ring and Ball (R&B) softening point in the range of 75 to 110 DEG C, b) a weight average molecular weight (Mw) of 1000 to 2600 Dalton, a z-average molecular weight (Mz) from 1900 to 5000 Dalton and an Mw/Mn below 2.0, c) a level of aromatic protons below 1.5 % with respect to the total protons determined by <1>H-NMR, and d) a mixed methylcyclohexane aniline cloud point (MMAP) of 90 DEG C or less. The resins according to the invention are characterized by a high amount of cyclic structures. Further disclosed is a method of independently controlling the R&B softening point and the molecular weight of an aliphatic resin composition during its preparation by polymerization of a petroleum-based feed, the method being characterized in that the amount of cyclic structures in the resins is increased.