摘要:
Use of nanoparticles of barium sulfate or of calcium carbonate, with a particle size of less than or equal to 150 nm and greater than or equal to 0.5 nm, as filler in transparent polymer compositions. The compositions obtained simultaneously show good scratch resistance, good impact strength, good tensile strength, good heat stability and good visible and UV radiation stability, while at the same time conserving excellent transparency. The compositions may be used as replacement materials for glass in the motor vehicle sector and in the optics sector.
摘要:
A method of preparing a transparent polymer material includes i) obtaining composite nanoparticles having mineral nanoparticles at least partially coated with at least one monomer and/or at least one polymer suitable for promoting physicochemical interactions at the interface between the mineral nanoparticles and a thermoplastic polycarbonate matrix, the mineral nanoparticles being surface-modified by the monomer and/or the polymer, either directly by grafting or directly by adsorption of the monomer and/or polymer onto the surface of the mineral nanoparticles; or via a coupling agent selected from a chlorosilane or an organosilane including a functional group that is capable of reacting by a radical pathway. The composite nanoparticles obtained in step i) are mixed with the thermoplastic polycarbonate matrix in the molten state to obtain the transparent polymer material.
摘要:
A method of preparing a transparent polymer material includes mixing mineral nanoparticles selected from nanoparticles of alkaline-earth metal carbonates, alkaline-earth metal sulfates, metallic oxides, oxides of metalloids, and siloxanes, and a composition A including at least one thermoplastic polymer in the molten state selected from polycarbonate (PC), polystyrene (PS) and polymethyl methacrylate (PMMA) in order to obtain a master-batch, the mixture of step i) including at least 25% and at most 75% by weight of the mineral nanoparticles. The master-batch obtained in step i) is mixed with a composition B of a thermoplastic polycarbonate matrix (PCm) in the molten state, to obtain a transparent polymer material including at most 10% by weight of the mineral nanoparticles, preferably at most 5% by weight of the mineral nanoparticles.
摘要:
A method of preparing a transparent polymer material includes mixing mineral nanoparticles selected from nanoparticles of alkaline-earth metal carbonates, alkaline-earth metal sulfates, metallic oxides, oxides of metalloids, and siloxanes, and a composition A including at least one thermoplastic polymer in the molten state selected from polycarbonate (PC), polystyrene (PS) and polymethyl methacrylate (PMMA) in order to obtain a master-batch, the mixture of step i) including at least 25% and at most 75% by weight of the mineral nanoparticles. The master-batch obtained in step i) is mixed with a composition B of a thermoplastic polycarbonate matrix (PCm) in the molten state, to obtain a transparent polymer material including at most 10% by weight of the mineral nanoparticles, preferably at most 5% by weight of the mineral nanoparticles.
摘要:
A method of preparing a transparent polymer material includes i) obtaining composite nanoparticles having mineral nanoparticles at least partially coated with at least one monomer and/or at least one polymer suitable for promoting physicochemical interactions at the interface between the mineral nanoparticles and a thermoplastic polycarbonate matrix, the mineral nanoparticles being surface-modified by the monomer and/or the polymer, either directly by grafting or directly by adsorption of the monomer and/or polymer onto the surface of the mineral nanoparticles; or via a coupling agent selected from a chlorosilane or an organosilane including a functional group that is capable of reacting by a radical pathway. The composite nanoparticles obtained in step i) are mixed with the thermoplastic polycarbonate matrix in the molten state to obtain the transparent polymer material.
摘要:
Process for making a solid compound by precipitation, using a high intensity mixing reactor and comprising the steps of (A) introducing a first fluid material containing a first reactant and a second fluid material containing a second reactant into said reactor, in order to obtain a mixed fluid, in order to cause the first reactant to react with the second reactant to form a solid compound by precipitation in the mixed fluid; (B) withdrawing the mixed fluid containing the precipitated solid obtained in step (A) from the reactor, and; (C) optionally separating the precipitated solid compound from at least one fraction of the mixed fluid.
摘要:
A device is disclosed for separating, orienting and positioning axes including at least one operational flat. The device includes a static chute equipped with a wide bottom opening closed by a drawer which is moved with a back and forth motion from a withdrawn position in which it unveils a narrow opening which is large enough to enable the fall of a single axis onto rolling blades which are extended by descending ramps bringing each axis onto two bearing-sliding blades. The bearing sliding blades cooperate with two push plates, as well as a trap borne by the drawer, to produce the roll of the axis in the desired direction, followed by the slide of that axis without rotation to a selected position.
摘要:
The invention concerns an optocoupler. The optocoupler includes a substrate made of optically opaque electrically insulating material metallized to provide conductive traces on a top surface thereof which are electrically linked to metal pads on a bottom surface. A cadmium sulfoselenide photoresistor having an active surface is placed over the substrate with the active surface facing the substrate where the photoresistor has two electrodes. Metal leads connect each of the two electrodes of the photoresistor to two metallized traces on the substrate. A light emitting diode (LED) chip is mounted on the substrate facing the active surface of the photoresistor. The LED chip has a top and bottom electrode, where the bottom electrode is electrically attached to a third metallized trace and the top electrode is wire bonded to a fourth metallized trace. A cover made of optically opaque material is fixed to the substrate so as to enclose the photoresistor and the LED chip in a light tight enclosure. In an alternative embodiment of the invention, the photoresistor and the LED chip can lie side by side and be in optical communication with each other through a reflective coating on the inside of the cover.
摘要:
A metal body is inspected for defects by relatively longitudinally displacing it and a plurality of pairs of coils connected in respective bridge circuits that are excited with alternating current. The coils are also excited with alternating current so that eddy-current variations caused by defects in the body become impedance variations of the coils which in turn become imbalance signals in the respective bridges. The imbalance signals are demodulated to form respective imbalance voltages which are periodically sampled and the levels of the sampled demodulated voltages are stored. The sampled demodulated voltages of each bridge are averaged to produce respective base lines which are compared with the respective stored levels of each sampled voltage for generation of respective error signals corresponding to the differences. These error signals are compared with a first relatively low threshold corresponding to the smallest defect to be detected and with a second relatively high threshold. When one of the error signals exceeds only the first threshold it indicates a small defect at the respective location on the body and when one of the error signals exceeds the second threshold it indicates a large defect. A longitudinal succession of at least abutting zones is established on the body and the error signals for each zone are summed. Each of these sums is compared with a predetermined third threshold and when one of the sums exceeds the third threshold it indicates a long defect in the respective zone.
摘要:
A device for separation, orientation, and positioning of parts essentially flat in their general shape, characterized by the fact that the parts are supplied in flat position upon a storage rail and that the device includes, in combination, a tilter which can be activated by a piston between an initial, raised position and a second, tilted position, with the tilter including a support forming a continuation of the storage rail when the tilter is in raised position so as to receive the first of parts from the reserve, with stops arresting the rest of the parts, and with the support further including retaining members (9) for preventing the part from being dislodged, while stop pads stop the first part remaining on the rail during tilting of the tilter.