Binder of vegetable origin, compositions comprising same and method for reducing the amount of petroleum-based bitumen

A binder of vegetable origin comprising:

• 65% to 85% of a plasticizing fraction comprising a modified tall-oil pitch;
• 15% to 35% of a structuring fraction comprising a modified vegetable resin;
• the % being % by weight relative to the weight of the binder
• wherein the modified vegetable resin is a phenolic terpene resin or a fortified-rosin ester,
• the fortified-rosin ester being a modified vegetable resin obtained by esterification reaction of a polyol with a fortified rosin,
• the fortified rosin being a modified vegetable resin obtained by chemical reaction of Diels-Alder type of a rosin with a compound selected from acrylic acid, methacrylic acid, fumaric acid, itaconic acid, sorbic acid, maleic acid, or anhydride forms thereof,
• the polyol esterifying the fortified rosin being selected from pentaerythritol, 1,1,1-trimethylolpropane, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, glycerol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, and mixtures thereof.