摘要 |
Inert esters of rosin and a primary polyhydric alcohol, such as rosin-pentaerythritol esters, are modified by reacting commercially available rosin esters which contain residual hydroxyl groups with a lower aliphatic carboxylic acid or anhydride, for example, acetic anhydride or propionic anhydride, to substantially completely esterify the residual hydroxyl groups. The resulting inert, completely esterified rosin esters, when formulated with non-polar natural rubber or SBR in adhesive systems, results in a time-stable tack value not available with conventional rosin esters.
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