C-5 aliphatic resins

The resin is dissolved in the test solvent either at room temperature or at elevated temperature. The solution is then cooled and the temperatures at which an initial and full cloud appears are recorded. Low cloud points indicate good solubility in that solvent type and predict good solubility of that resin in elastomers of the same chemical nature. As a rule of thumb, cloud points greater than 70 C indicate poor compatibility while cloud points less than 0°C indicate excellent compatibility. Table 2 shows cloud points for four types of resins—rosin esters (Staybelite 10 Ester and Foral 85, 105), pure monomer aromatics (Piccotex), polyterpene resin (Piccolyte), and C-5 aliphatic resins (Pic-copale, Piccotac). The low cloud points of the rosin esters in all blends predicts that rosin es-... 

Table 4 shows the effect of molecular weight and molecular weight distribution on the tack-ifying effectiveness of three C-5 aliphatic resins. These three resins have softening points in the range of 92-100°C. Based on chemical... 

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