Abstract: For the semi-continuous production polyadducts of alkylene oxide by an addition reaction of alkylene oxide on a chain initiator having at least one active hydrogen, there is provided a reactor (1) constituted by a cylindrical body with two diameters, the upper part being of larger diameter than the lower part, heat-exchange means (2) and recycling ducts (13, 15) for the recycling of the reaction mixture from the bottom to the head of the reactor in order to obtain the final desired product, thereby enabling the production to be carried out with greater flexibility and reduced down times.

Abstract: A continuous process for the production of polyadducts of alkylene oxide on a chain initiator with at least one active hydrogen comprises the step of: (a) providing n reaction units constituted by a tubular reactor (11), and a heat exchanger (14) downstream of the tubular reaction (11); (b) supplying the preheated chain initiator and the alkylene oxide to the reactor of the first reaction unit; (c) reacting the chain initiator with the alkylene oxide to obtain a first mixture; (d) cooling the first mixture by means of the heat exchanger (14); (e) supplying the reactor of the following reaction unit with the cooled mixture and with alkylene oxide; (f) repeating the procedure until the last reaction unit and then discharging the last mixture containing the desired product. The tubular reactors are vertical and the chain initiator and alkylene oxide are sprayed into the top of the reactor where a gas liquid reaction occurs.

Abstract: The present invention relates to apparatus for the semi-continuous polymerization of monomers with the use of a chain initiator. This apparatus is characterized in that it comprises a reactor (1) arranged with its axis substantially vertical and defining a lower, frustoconical part (III), an upper atonization part (I) and an intermediate part (II), the reactor (1) having monomer and initiator inlet apertures (8, 10, 20, 21) at least one outlet aperture (12), a recycling duct (15) connected at one end to the outlet aperture (12) and at the other end to the upper part (I) through at least one atomizer (9), and a stirrer (25). The apparatus according to the invention has the particular advantage of being usable for reactions with any type of chain initiator and catalyst, whether they are solid, liquid or in suspension.