摘要:
A water- and solvent-free release agent for use in the production of articles of polyurethane foam contains one or more polyenes as the main constituent and also in addition if required a consistency adjuster, an antioxidant, accelerators and/or stabilizers. To apply water- and solvent-free release agents to the surfaces of polyurethane-foam moulding dies the misting or atomization of the release agent is effected with a device with an electrostatic charge, by which the release agent particles are given an electrostatic charge when passing through the exit nozzle.
摘要:
A process for producing polyurethane foam articles is described, in which the article is produced in the conventional manner by foaming in a mould and a release agent is applied to the mould surface prior to filling with the foam-producing components. According to the invention, a solvent-free, aqueous release agent is used in combination with one or more alkali metal and/or ammonium salts of higher fatty acids and one or more higher alcohols and the combination is applied in the hot state, preferably at a temperature of at least 75.degree. C. to the mould surface. In addition, an additive is described, which is suitable for performing the process according to the invention and contains one or more alkali metal and/or ammonium salts of higher fatty acids, one or more higher alcohols and otherwise water. The process according to the invention has the advantage that it not only avoids the use of environmentally prejudicial organic solvents, but also leads to excellent release agent films, from which the water is very largely evaporated within a very short time and namely within the very short cycle times of modern foam plants.
摘要:
A process for producing polyurethane foam articles is described, in which the article is produced in the conventional manner by foaming in a mould and a release agent is applied to the mould surface prior to filling with the foam-producing components. According to the invention, a solvent-free, aqueous release agent is used in combination with one or more alkali metal and/or ammonium salts of higher fatty acids and one or more higher alcohols and the combination is applied in the hot state, preferably at a temperature of at least 75.degree. C. to the mould surface. In addition, an additive is described, which is suitable for performing the process according to the invention and contains one or more alkali metal and/or ammonium salts of higher fatty acids, one or more higher alcohols and otherwise water. The process according to the invention has the advantage that it not only avoids the use of environmentally prejudicial organic solvents, but also leads to excellent release agent films, from which the water is very largely evaporated within a very short time and namely within the very short cycle times of modern foam plants.
摘要:
A release agent is described, which is suitable for the production of polyurethane foam articles in molds. It is an aqueous emulsion or dispersion of per se known release-effective substances as well as optionally conventional additives, having a water content of at least 60% by weight and preferably 85 to 96% by weight, the water being masked through the effect of lyotropic mesomorphism. Masking and immobilizing the water molecules avoids that the water molecules have a prejudicial effect of the polyol/isocyanate reaction, and is preferably achieved by the combined use of release-effective substances and suitable masking aids. As suitable masking aids especially fatty alcohol polyglycol ethers and ethoxylated fatty alcohols are proposed. The polyurethane articles obtained while using the above described release agent fulfil the standard quality requirements without any of the disadvantageous effects on the environment such as occur with conventional release agents.
摘要:
A device and a method for actuating an injector in a fuel-injection system of an internal combustion engine are described. Using a first calibration method and based on a control parameter, an injector parameter which characterizes the injection process is determined. Starting from this injector parameter, a first feature is determined for calibrating the injector. A second calibration method determines a second feature for calibrating the injector, based on an engine parameter. The first calibration method is monitored on the basis of the second feature.
摘要:
A method for operating an internal combustion engine in HCCI mode, including: a) sensing a profile of a measured variable of a variable in a combustion chamber of a cylinder; b) identifying combustion feature(s) of a combustion event in a first combustion cycle based on the profile; c) modeling a first value of a state variable at a defined point in time after the first combustion cycle and before a second subsequent combustion cycle based on the identified combustion feature(s); d) determining desired target values of combustion feature(s) of a combustion event in the second subsequent combustion cycle; e) modeling a second value of the state variable at the defined point in time based on the target values; and f) applying control to the internal combustion engine starting at the defined point in time as a function of the first and the second value of the state variable.
摘要:
The present invention relates to a process for preparing radiation-curing binders containing allophanate groups by reacting, at temperatures of ≦130° C., A) one or more compounds containing uretdione groups with B) one or more OH-functional compounds which contain groups which react, with polymerization, with ethylenically unsaturated compounds on exposure to actinic radiation (radiation-curing groups), C) optionally NCO-reactive compounds other than B), in the presence of D) a catalyst containing at least one zinc compound, to form allophanate groups by opening the uretdione ring. The present invention also relates to the binders obtained by the process of the invention and to coating compositions containing these binders.
摘要:
A method for regulating HCCI combustion of fuel in a reactor of an internal combustion engine is described in which a multivariable regulation is used, manipulated variable changes Δuk for the instantaneous regulating cycle k being determined on the basis of at least system deviations Δxk-1 and manipulated variable changes Δuk-1 of a preceding regulating cycle k−1.
摘要:
This invention relates to DVDs made from polycarbonate and a special UV curable bonder material consisting of A) an urethane acrylate oligomer as binder, which is the reaction product of i) one or more polyisocyanates and ii) one or more hydroxyfunctional lactone ester (meth)acrylates having a number average molecular weight of from 200 g/mol to 2000 g/mol and having the formula: CH2═C(R1)—C(O)—O—R2—[O—C(O)—R3]n—OH wherein, n is an integer from 1 to 5, R1 is hydrogen or methyl, R2 represents an alkylene group or substituted alkylene group having from 2 to 10 carbon atoms and R3 represents a straight or branched chain alkylene group of from 3 to 8 carbon atoms, and which may be substituted with one or more alkyl groups having from 1 to 12 carbon atoms, B) a reactive thinner, comprising of mono functional acrylates and/or (meth)acrylates C) a photo initiator and D) optional additives which offers improved performance at high data transfer rates.
摘要:
A process for the salt-free coagulation of polymer dispersions in a rotor/stator assembly is disclosed. The rotor/stator assembly includes a casing, a rotor shaft rotatably mounted within the casing, a rotor having a conical surface affixed to the rotor shaft, and a stator affixed to the casing and concentrically associated with the rotor. The conical surface faces a surface of the stator to form an adjustable shear gap, which is surrounded by an annular space. A polymer dispersion is fed into the assembly and conveyed through the shear gap. During this conveyance, the polymer dispersion is precipitated at a predetermined shear rate and a predetermined shear deformation. The polymer dispersion is discharged from the assembly through an outlet neck, and the assembly is flushed with water using one or more ports formed in at least one of a pipeline coupled to the axial feed neck, the stator, and the casing.