TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The method comprises mixing and heating the precursors, catalysts and organic initiators in a closed gas-tight reactor to reach the reaction temperature and autogenous pressure that is greater than the atmospheric pressure in the closed reactor, then producing leakage of gas composition so as to reduce the pressure in the reactor at reaction temperature and maintaining the reaction temperature in the reactor for greater than 5 minutes. Preferred Components: The organic initiator consists of amino-alcohols having at least one amine consisting of primary amines, secondary amines and tertiary amines and having main chain of 2-10 carbon atoms, is triethanolamine, and preferably consists of 1-amino-1-cyclopentanemethanol, 4-aminocyclohexanol, amino-1-butanol, 2-amino-1-butanol, 2-amino-1-phenyl-1,3-propanediol, 3-amino-3-phenylpropan-1-ol, and 2-amino-3-phenyl-1-propan-1-ol. The catalyst consists of zinc sulfate and zinc stearate. The alpha / alpha -alkoxylated glycerol linear carbonic ester compound is of formulae (M1-O-CH2-CH(CH2-O-CR4R5R6)-O-C(=O)-O-Q1) (III), (M1-O-CH(CH2-O-CR4R5R6)-CH2-O-C(=O)-O-Q1) (IV), (M1-O-(G1-O-(C(=O)-O)x)p-Q1) (VI), (M1-O-(G1-O-C(=O)-O)n-Q1) (V).p = greater than or equal to 1;x = 0 or 1 that varies in formula (VI) according to each group of formula (-G1-O-(C(=O))x) (VI-a);G1 = alpha / alpha -alkoxylated propyl group of formula (-CH2-CH(CH2-O-CR4R5R6)-) (IIa);n = greater than or equal to 1;R4-R6 = H or organic group of formula (-CH2-(CH2-CH2-X)m-R7) (VII);R7 = H or 1-6C-hydrocarbyl;m = 0-10; andX = -O- or -NH-. EXAMPLE - Methyl ether of cyclo-carbonate glycerol, ethanolamine (2-amino-1-ethanol) as an oligomerization initiator and an amount of zinc stearate were placed in 250 ml autoclave. After the reaction, the mass proportion of methyl ether of cyclo-carbonate glycerol was 85/15 and the proportion of catalyst was 0.5% with respect to the total weight of the reactants. After hermetically sealed the autoclave, the autoclave was heated so as to bring the temperature of the reaction medium to 180 degrees C and at atmospheric pressure. The temperature was maintained for 2 hours under mechanical rotary agitation at a speed of 400 revolutions per minute and worked upto give alpha / alpha -alkoxylated glycerol linear carbonic esters in the form of oligomer with average molecular weight of 2460 g/mole.