摘要:
A liquid-phase chemical reaction medium comprises one or more reactants, optionally in the presence of a reaction product(s) and one or more solvents, diluents or other form of liquid carrier, a catalyst system comprising at least a metal or metal compound and optionally further compounds such as ligands or complexing agents; characterised in that the reaction medium further comprises a polymeric dispersant dissolved in said liquid carrier, said polymeric dispersant being capable of stabilising a colloidal suspension of particles of said metal or metal compound within the liquid carrier. The presence of the polymeric dispersant enables metal formed by catalyst deactivation to be more easily recovered and recycled. Preferably, the polymeric dispersant has sufficiently acidic or basic functionality to stabilise the colloidal suspension of said metal or metal compound.
摘要:
A process for the carbonylation of a conjugated diene is described. The process comprises the steps of reacting a conjugated diene with carbon monoxide and a co-reactant having an active hydrogen in the presence of a solvent system and a catalyst system. The solvent system comprises a an aromatic carboxylic acid or, under some conditions, any carboxylic acid. The catalyst system is obtainable by combining: a. a metal of Group 8, 9 or 10 or a compound thereof: and b. a bidentate ligand of general formula (I) X1(X2)- Q2 - A - R- B - Q1 - X3(X4) (I) A and B each independently represent lower alkylene linking groups; R represents a cyclic hydrocarbyl structure to which Q1 and Q2 are linked, via the said linking group, on available adjacent cyclic atoms of the cyclic hydrocarbyl structure; the groups X1, X2, X3 and X4 independently represent univalent radicals of up to 30 atoms having at least one tertiary carbon atom or X1 and X2 and/or X3 and X4 together form a bivalent radical of up to 40 atoms having at least two tertiary carbon atoms wherein each said univalent or bivalent radical is joined via said at least one or two tertiary carbon atoms respectively to the appropriate atom Q1 or Q2; Q1 and Q2 each independently represent phosphorus, arsenic or 120 antimony; and, optionally, a source of anions. When the ratio of bidentate ligand : group 8, 9 or 10 metal is greater than 10:1 (mol:mol), the reaction proceeds with any carboxylic acid.
摘要:
A process for the carbonylation of ethylenically unsaturated compounds including vinyl esters and a process for the production of 3-hydroxy propanoate esters or acids. The process comprises reacting said compound with carbon monoxide in the presence of a source of hydroxyl groups and of a catalyst system. The catalyst system is obtainable by combining: (a) a metal of Group 8, 9 or 10 or a compound thereof: and (b) a bidentate ligand of general formula (I): X1(X2)-Q2-A-R—B-Q1-X3(X4).
摘要:
An embedment casting composition and a process of embedding a specimen in an acrylic polymer matrix is described. The composition comprises an acrylic copolymer and a suitable solvent. The acrylic copolymer is derived from 80-99% w/w methyl methacrylate, 0.1-10% w/w of a C3-C10 olefinically unsaturated acid co-monomer selected from carboxylic, phophonic, sulphonic or phosphinic acids and 0-10% w/w other suitable monomers and/or additives. A process of embedding a specimen in an acrylic polymer matrix, a cast of an embedded metal specimen, the use of an embedment composition for coating a specimen prior to an embedment coating process and use of an embedment composition as the copolymer resin component of an embedment slurry are also described.
摘要:
A process for the alkoxycarbonylation of a vinyl ester comprising reacting a vinyl ester with carbon monoxide in the presence of an alkanol and a catalyst system. The catalyst system used in the said process is obtainable by combining: a) a metal of Group VIII B or a compound thereof, and b) a bidentate ligand of general formula (I) wherein, R is a covalent bridging group; R1 together with Q2 to which it is attached form an optionally substituted 2-Q2-tricyclo[3.3.1.1 {3,7}]decyl group or derivative thereof(2-PA); R2 and R3 independently represent univalent radicals upto 20 atoms or jointly form a bivalent radical of up to 20 atoms; and Q1 and Q2 each independently represent phosphorous, arsenic or antimony. The process is carried out for the production of a 3-hydroxy propanoate ester or acid of formula (II) CH2 (OH)CH2 C(O) OR28. The process may also be carried out for the production of a lactate ester or acid of formula (III).
摘要:
An edge lit illumination device is described. The device has at least one light source and a light transmission element having at least one light output surface and at least one light ingress edge substantially perpendicular to said surface. The light source is located adjacent to the light ingress edge so that light from the light source enters the transmission element via the said edge and propagates through the element. The light output surface is uniformly roughened across the output surface. The roughening is sufficiently fine to give an average Ra value across the surface of less than 1.0 mum/mm thickness of the element or drop-off of light output across the surface of less than 5000 lux.
摘要:
A mould for moulding, for example, an acrylic worktop for a kitchen comprises two mould halves which include a mould base (2) and mould top (4) arranged to co-operate with one another to define a mould cavity into which polymerisable material may be input. The surface of mould halves which contacts the polymerisable material comprises a composite material (6) which comprises extruded polypropylene sheet with a polyester fabric laminated to one side. The sheet is supported by means of supports (8) which are retained in position by a layer (10) of GRP. After input of the polymerisable material into the mould cavity, it is allowed to cure to define a product from which the mould base and top may be removed. The product may then be placed in an oven at about 120 °C to fully cure it. In another embodiment described, a mould comprises two mould halves made by thermoforming or vacuum forming polypropylene sheet.
摘要:
The present invention provides a process for the hydroformylation of ethylenically unsaturated compounds, which process comprises reacting said ethylenically unsaturated compound with carbon monoxide and hydrogen, in the presence of a catalyst system and a solvent, the catalyst system obtainable by combining: a) a metal of Group VIII or a compound thereof; and b) a bidentate phosphine, the process characterised in that a chlorine moiety is present in at least one of the said Group VIII metal compound or said solvent.
摘要:
A polymeric material containing a halogen-containing polymer such as PVC, an inorganic hydroxide and, an acrylic material is described. The presence of the inorganic hydroxide provides a material of superior weathering resistance as compared to materials comprising halogen-containing polymers which do not contain hydroxide.