TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The catalyst used in the alcoholysis reaction is inorganic base or organo tin. The inorganic base is chosen from alkali hydroxide or alkali alkoxide. The alkali hydroxide is chosen from sodium hydroxide, potassium hydroxide and lithium hydroxide. The alkali alkoxide is chosen from sodium methoxide, sodium alcoholate, and dehydration product of potassium methoxide and hydroxide. The organo tin is chosen from tetrachloride, stannous octoate and dibutyl tin laurate. The weight of the catalyst is 0.005-1.3 wt.% of jatropha curcasl oil and alcoholysis agent. The mineral acid catalyst is sulfuric acid or phosphoric acid, and its dosage is 0.1-5 wt.% of the fatty acid mixed.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The bio-polylol with high molecular weight is formed by the addition reaction of bio-polylol and oxy- alpha -olefin in the presence of catalyst. The alcoholysis reaction is performed at 65-240 degrees C for 1-16 hours. The epoxidation reaction is carried out using organic acid, hydrogen peroxide and fatty acid in the presence of mineral acid catalyst. The epoxidation reaction is performed at 30-70 degrees C for 2.5-12 hours. The temperature for ring cleavage reaction is controlled at 65-180 degrees C and the reaction time is 1-10 hours. Preferred Compounds: The alcoholysis agent used is hydramine or alcohol. The hydramine is chosen from isopropanolamine, diisopropanolamine, triisopropanolamine, neovaricaine, diethanolamine, trolamine, methyl diethanolamine, methyl diisopropanolamine, alkyl alkanolamine and phenmethyl alkanolamine, preferably triisopropanolamine, diisopropanolamine, trolamine and diethanolamine. The alcohol is chosen from methanol, ethanol, propanol, butanol, 1,4-butanediol, diglycol, triglycol, glycol, propanetriol, propanediol, pentaerythritol, xylitol and sorbierite, preferably propanediol, butanediol butylene glycol, diglycol, triglycol, glycol, propanetriol and trimethylolpropane. The mol ratio between alcoholysis agent and jatropha curcasl oil is (2.0-5.7):1. The organic acid used in the epoxidation reaction is formic acid or acetic acid. The amount of organic acid is 0.5-3.0 times the unsaturated double bond of fatty acid mixed. The amount of hydrogen peroxide is 1.0-1.5 times the amount of unsaturated double bond of fatty acid mixed. The mol ratio between ring opening agent and mixed epoxidized fatty acid ester is (0.8-1.6):1. The oxy- alpha -olefin in addition reaction is ethylene epoxide, propylene epoxide and/or oxybutylene. The ratio of oxy- alpha -olefin is computed according to designed hydroxyl value of bio-polylol, and the weight of the oxy- alpha -olefin added in bio-polylol per mol is 1.0-1.22. The addition reaction is performed at 80-150 degrees C at pressure less than 1.0 MPa, for 2-6 hours.