Abstract: Anisotropic membranes particularly useful in reverse osmosis because of their good salt rejection properties and high transmission rate are provided which consist essentially of a polymer comprising a plurality of units of the formula ##STR1## in which each of the symbols Q, Q' and Q", which can be identical or different, represents a hydrogen atom, an alkyl radical with 1 to 4 carbon atoms or a --SO.sub.3 H radical, the number of --SO.sub.3 H radicals in the polymer being such that the ionic capacity of the polymer is from about 0.5 to about 5 meg/g, in the form of a layer which exhibits a degree of salt rejection, said layer having an equivalent thickness of from about 0.01 to about 5.mu. , and a highly porous support layer, of thickness up to about 1 mm.

Abstract: Four component polymerization initiators for olefinic monomers comprise (1) an oxidizing agent such as hydrogen peroxide, a persulphate, a permanganate, a chlorate, a perchlorate, a bichromate, a bromate, a ceric salt, an oxazirane, an organic peroxide or an organic hydroperoxide, (2) a chelate compound of a metal such as titanium, iron, vanadium, aluminum, tin, manganese, chromium, cobalt, copper, zinc or bismuth in which the metal is not fully coordinated, (3) an electron donor in amount at most equal to that required to complex completely the said metal of the chelate compound, the said electron donor being for example an amine, a monoalcohol, an ether, an aldehyde, a ketone, an imine, an oxime, an amide, a sulphonamide, or a phosphonamide, and (4) a chelate complex or salt which is different from the chelate compound (2) and in which the metal may be for example, copper, iron, magnesium, manganese, chromium, vanadium or tin, the degree of coordination of the said metal being different from that of the met

Abstract: Olefines of at least 3 carbon atoms are oxidised e.g. to ketones or epoxy compounds using, as oxidising agent, uranium oxide, hafnium oxide or an oxo-metal compound of formula[[(L).sub.x (O).sub.n M-Q].sub.p M(O).sub.n (L).sub.x ].sup.m Ain which M represents Ti, Zr, Hf, V, Nb, Ta, Mo, W or U, L represents a monodentate or polydentate ligand, A represents an organic or inorganic anion or cation, Q represents oxygen or sulphur, x is an integer greater than or equal to zero, p is equal to zero or one, m is a positive or negative integer and there is one or more oxygen atoms directly bonded to the metal and not bonded to an organic radical.Typical oxidants are vanadyl-, zirconyl-, titanyl-, molybdyl-, tungstyl- and uranyl-acetylacetonate.