Abstract:
This thermoplastic elastomer is present in a substantially solid state suitable for use as a binder for a propellant, explosive, and/or gas generant of a supplemental restraint system. The thermoplastic elastomer is formed from a composition including A blocks which are crystalline at temperatures below about 75° C. and B blocks which are amorphous at temperatures above about −20° C. The A blocks are derived from oxetane derivatives and the B blocks are derived from oxiranes and derivatives thereof. The A blocks and B blocks are end-capped with a diisocyanate having a first isocyanate moiety that is substantially more reactive with the terminal groups of the blocks than the second isocyanate moiety, whereby the more reactive first isocyanate moiety is capable of reacting with the terminal groups of the blocks, leaving the less reactive second isocyanate moiety free and unreacted. The end-capped A blocks and the end-capped B blocks are linked together with a linking compound having two isocyanate-reactive groups which are sufficiently unhindered to react with the free and unreacted isocyanate moieties of the end-capped polymers.
Abstract:
This thermoplastic elastomer is present in a substantially solid state suitable for use as a binder for a propellant, explosive, and/or gas generant of a supplemental restraint system. The thermoplastic elastomer is formed from a composition including A blocks which are crystalline at temperatures below about 75° C. and B blocks which are amorphous at temperatures above about −20° C. The A blocks are derived from oxetane derivatives and the B blocks are derived from oxiranes and derivatives thereof. The A blocks and B-blocks are end-capped with a diisocyanate having a first isocyanate moiety that is substantially more reactive with the terminal groups of the blocks than the second isocyanate moiety, whereby the more reactive first isocyanate moiety is capable of reacting with the terminal groups of the blocks, leaving the less reactive second isocyanate moiety free and unreacted. The end-capped A blocks and the end-capped B blocks are linked together with a linking compound having two isocyanate-reactive groups which are sufficiently unhindered to react with the free and unreacted isocyanate moieties of the end-capped polymers.
Abstract:
This thermoplastic elastomer is present in a substantially solid state suitable for use as a binder for a propellant, explosive, and/or gas generant of a supplemental restraint system. The thermoplastic elastomer is formed from a composition including A blocks which are crystalline at temperatures below about 75° C. and B blocks which are amorphous at temperatures above about −20° C. The A blocks are derived from oxetane derivatives and the B blocks are derived from oxiranes and derivatives thereof. The A blocks and B-blocks are end-capped with a diisocyanate having a first isocyanate moiety that is substantially more reactive with the terminal groups of the blocks than the second isocyanate moiety, whereby the more reactive first isocyanate moiety is capable of reacting with the terminal groups of the blocks, leaving the less reactive second isocyanate moiety free and unreacted. The end-capped A blocks and the end-capped B blocks are linked together with a linking compound having two isocyanate-reactive groups which are sufficiently unhindered to react with the free and unreacted isocyanate moieties of the end-capped polymers.
Abstract:
Automotive airbag gas generant formulation providing alternative to commercially used formulations containing sodium azide. The composition comprises from about 25% to about 75% by weight of a heterocyclic compound having the following structure: ##STR1## wherein R is selected from hydrogen,--CO.sub.2 X, and--OXand X is a cation providing an anhydrous salt. The other principal ingredient of the composition is from about 25% to 75% by weight of an anhydrous oxidizing salt having a cation selected from metals of Group I-A of the Periodic Table (except sodium), calcium, strontium, or barium, and an anion which is essentially free of carbon, hydrogen, or halogens. From about 0% to 2% of a binder can be added, if necessary. An automotive airbag inflator containing the composition and a method for generating gas comprising the step of igniting the composition stated above are also disclosed.
Abstract:
A fastener assembly in which a fastener is adhesively secured within a borehole. A fastener having a shank with longitudinal channels is inserted within a borehole. A fluent adhesive is forced along the longitudinal channels of the fastener to occupy the space within the bore adjacent to the fastener. The adhesive is permitted to harden in situ so as to provide a strong chemo-mechanical bond.
Abstract:
A method and system for beamforming a multi-element array using time delays is provided. The array includes transmit array elements and receive array elements. Each of the array elements includes a processor. Modulation and demodulation functions are performed at the processors of each array element. The modulation and demodulation functions utilize receive time offsets and phase shifts, and transmit time offsets and phase shifts, respectively. The receive time offsets and phase shifts, and the transmit time offsets and phase shifts are determined by a central processing unit in order to beamform received signals and transmitted signals, respectively. The array elements are arranged in a daisy chain fashion in order to facilitate communication of control parameters, communication of bits to be transmitted and distributed combining of demodulated baseband samples from one array element to another and communicating the combined samples to the central processing unit.
Abstract:
A tool for securing or removing a cylindrical object by grasping the object and rotating it about its central axis comprises a band clamp assembly and a hinged drive assembly. The band clamp assembly comprises a band clamp which is tightened by means of a thumbscrew or hex nut. The hinged drive assembly comprises at least four segments connected by at least three hinges. The end-segments of the hinged drive assembly have on their obverse surfaces raised slots through which the band clamp is slipped. The band clamp assembly then fits over and around a cylindrical object such as an oil filter canister. The clamp is tightened around the canister body such that the inner surface of the clamp and the reverse surfaces of the end-segments, which are knurled or scored, are in frictional contact with the canister wall. In the preferred embodiment--a hinged drive assembly having five segments connected by four hinges, rotation of the canister about its central axis is accomplished by one of three means. The tool may be engaged with a ratchet wrench, which fits into a square hole in the center mid-segment, or with a force bar implement, which slips through two rings attached to the obverse surface of the center mid-segment. Torque also may be applied manually by grasping the center mid-segment and employing the necessary wrist action.
Abstract:
A method of preparing a thermoplastic elastomer having A blocks and at least one B block, wherein said A blocks are crystalline at temperatures below about 60.degree. C. and said B block is amorphous at temperatures above about -20.degree. C., said A blocks each being polyethers derived from monomers of oxetane and its derivatives and/or tetrahydrofuran and its derivatives, the method comprising:providing monofunctional hydroxyl terminated A blocks which are crystalline at temperatures below about 60.degree. C. and separately providing di-, tri- or tetrafunctional hydroxyl terminated B blocks which are amorphous at temperatures above about -20.degree. C.,end-capping said A blocks by separately reacting said A blocks with a difunctional diisocyanate in which one isocyanate moiety is at least about five times as reactive with the terminal hydroxyl group of the A blocks as the other isocyanate moiety, whereby the more reactive isocyanate moiety tends to react with the terminal hydroxyl group of the A blocks, leaving the less reactive isocyanate moiety free and unreacted, andadding di-, tri- or tetrafunctional B block to the end-capped A blocks at approximately the stoichiometric ratios that they are intended to be present in the thermoplastic elastomer such that the free and unreacted isocyanate moiety on the end-capped A block reacts with a functional moiety of the B block to produce ABA or A.sub.n B thermoplastic elastomers.
Abstract:
A method of processing location information on a mobile device which includes a primary receiver for receiving a primary signal; a diversity receiver for receiving a diversity signal or location information; a diversity combiner which can combine primary and diversity signals to form a combined signal; and a first processing unit for processing the combined signal; the method comprising the steps of: identifying whether the device is in a location mode or a diversity mode; if the device is in location mode, disabling the diversity combiner; passing the output from the primary receiver directly to the first processing unit; and passing location information from the diversity receiver to a location processing unit.
Abstract:
A method is provided in which PGN is end-modified in a process using a single solvent. The resulting end-modified PGN may be stably crosslinked using aliphatic polyisocyanates. Further provided are methods of producing energetic compositions comprising PGN which has been end-modified in a process using a single solvent. Such energetic compositions may be stably crosslinked using aliphatic polyisocyanates.