摘要:
In a process for hardening phenol-formaldehyde resol resins, comprising conducting the hardening of the resins with an acidic solution of water and/or an organic solvent having dissolved therein an aromatic sulphonic acid and/or concentrated sulphuric acid, the improvement comprising the hardening in the presence of aniline added to the phenolic resin beforehand in a quantity of between about 0.5 and 2% relative to the weight of the phenolic resin whereby the pot life is extended and the cure time is satisfactory, the resultant products being especially useful as prepegs.
摘要:
An apparatus for evacuating the gases resulting from the decomposition of industrial process gases, such as ethylene, contained in a vessel under high pressure is adjacent to the vessel. The apparatus comprises:(1) at least one safety means separating the apparatus from the vessel;(2) a reservoir with a volume which is 2 to 100 times that of the vessel;(3) at least one connecting pipe between the vessel and the reservoir; and(4) at least one chimney between the reservoir and the atmosphere.The apparatus is useful for the recovery of decomposition gases for the purpose of preventing atmospheric pollution. The risk of explosion is reduced by evacuating decomposition gases through the apparatus.
摘要:
An embossed ethylene-propylene copolymer film having a thickness of less than or equal to 24 microns. A method and apparatus for making the film by blow-extruding the ethylene-propylene copolymer into a tubular web, pinching the tubular web between pinch rolls, and embossing the pinched web by passing it between an embossing roll and a pressure roll.
摘要:
A composition for the manufacture of hot-melt adhesives, in which the improvement comprises a terpolymer of ethylene having a melt index between 5 and 500 dg/minute and comprising from 1 to 10 mol % of units derived from an ester selected from alkyl acrylates and methacrylates, the alkyl group having from 1 to 6 carbon atoms, and from 0.3 to 3 mol % of units derived from maleic anhydride. The composition also contains at least one tackifying resin and may contain at least one compound selected from paraffin, microcrystalline polymeric wax, and esters of a hydrogenated rosinic acid and of a lower alcohol.
摘要:
The danger of explosion due to decomposition of high-pressure industrial process gases, such as ethylene, is reduced by maintaining in an inert atmosphere at least part of an evacuation system included between a pressurized vessel within which the decomposition may take place, on the one hand, and the atmosphere, on the other.The evacuation system to the atmosphere for the gases contained in the high-pressure vessel, includes(1) an evacuation pipe adjacent to the vessel;(2) a safety means separating the evacuation pipe from the vessel;(3) a sealing means located in the evacuation path of the gases and occupying the entire cross-section of the evacuation pipe;(4) a first gas supply circuit connected by a pipe to that part of the evacuation pipe that is located between the safety means and the sealing means, and means for the first supply pipe to control the volume of gas supplied by the first supply circuit; and(5) a second gas supply circuit connected by a pipe to the sealing system, and means for the second supply pipe to control the volume of gas fed by the second supply circuit.The apparatus is useful for the recovery of decomposition products for the purpose of averting atmospheric pollution, as well as for reducing the risk of explosion.
摘要:
A catalytic component having the formula(MX.sub.a) (MgX.sub.2).sub.b (RMgX).sub.c (MHgX).sub.dwherein M is a metal selected from group VI B and group V B of the Periodic Classification, X is a halogen, R is a hydrocarbon radical, 2.ltoreq.a .ltoreq.3.5, 1.ltoreq.b.ltoreq.30, 1.ltoreq.c.ltoreq.8 and 0.ltoreq.d.ltoreq.10 is prepared by reducing a metallic halide of the metal M, the valency of said metal being 4 if a metal of group IV B is concerned and 4 or 5 if a metal of group V B is concerned, by means of at least one organomagnesium compound having the formula RMgX, the said organomagnesium compound being used in the solid state and reduction of the metallic halide being carried out under a pressure lower than or equal to atmospheric pressure and at a temperature lower than the decomposition point of said organomagnesium compound under the pressure concerned but at least 10.degree. higher than the boiling point or sublimation point of the metallic halide under the pressure concerned.
摘要翻译:具有式(MXa)(MgX2)b(RMgX)c(MHgX)d的催化组分,其中M是选自元素周期分类的VIB族和VB族的金属,X是卤素,R是烃基, 通过还原金属M的金属卤化物来制备2 = a = 3.5,1,...,b = 30,1 = c = 8和0 = 如果涉及IVB族金属,所述金属的价数为4,如果涉及VB族金属,则为4或5,通过至少一种具有式RMgX的有机镁化合物,所述有机镁化合物用于 金属卤化物的固态和还原在低于或等于大气压的压力下进行,并且在相对压力下比所述有机镁化合物的分解点低的温度低至少比沸点高10℃, 金属卤化物在有关压力下的升华点。
摘要:
Shaped articles of polybut-1-ene are made by preheating a polymer blank in the crystalline form II at a temperature between 20.degree. and 90.degree. C. The preheated blank is then press-forged under a pressure between 8 and 100 kgf/mm.sup.2 for a period of 1-40 seconds. During the shaping operation, the polymer is converted into the crystalline form I. Polybut-1-ene shaped articles are formed that have a melting peak, determined by differential thermal analysis, at 119.degree. C.
摘要翻译:通过在20°至90℃的温度下预热结晶形式II的聚合物坯料制备聚丁-1-烯的成型制品。然后将预热的坯料在8-100kgf / mm 2之间的压力下锻造,以便 时间1-40秒。 在成型操作期间,将聚合物转化为晶型I.形成了在119℃下具有通过差示热分析确定的熔融峰的聚丁-1-烯形制品。
摘要:
New organo-lithium initiators, their synthesis, and their use. The initiators have the formula: ##STR1## in which R" is either a hydrogen atom or a methyl radical; either n is 1, in which case R'=H and m and p are integers, the sum of which is between 0 and 10 inclusive, or n is 2, R' then being an alkyl radical of 2 to 8 carbon atoms and m=p=o; and R is an alkyl radical of 1 to 4 carbon atoms.The initiators are prepared by reacting compounds of the formula; ##STR2## with an alkyl-lithium RLi in a non-polar solvent in the absence of any polar solvent or complexing agent.The initiators are used to prepare polydienes of high stereoregularity by reacting with a diene, and the polydiene is used to prepare a three-block or star copolymer by reacting with an anionically polymerizable monomer.
摘要:
Process and device for cooling a mixture of polymer and monomer from a reactor in which ethylene is polymerized or copolymerized at a pressure greater than 1,000 bars between a pressure-reduction valve located downstream of the reactor and a medium pressure separator. The cooling is achieved by injecting monomer at a pressure below that of the separator using a device with a nozzle cross-section S.sub.1 through which the mixture from the reactor passes, a convergent mixing zone in which the mixture is mixed with the monomer injected, which is supplied at a flow rate q, and a diffuser of throat cross-section S.sub.3, which makes it possible to bring the mixture to the pressure of the separator. The dimensions of the device are such that the ratio Q/S.sub.1 is between 0.20 and 1.35 t/hr.mm2 and the ratio (q+Q/S.sub.3 is between 0.1 and 0.3 t/hr.mm2.
摘要:
Radical polymerization of ethylene in the presence of an initiator and up to 500 ppm of a cyclic olefin having from 5 to 12 carbon atoms and a ring of 5 to 9 members or styrene and its alkyl homologues.