摘要:
A novel family of cycloalkanes compounds having one or more allylidene functionalities which can be used to create cross-linked thermosets and thermoplastics having thermal stability. An example heptacyclo [6.6.0.02,6.03,13.04,11.05,9.010,14] tetradecane (HCTD) complex with terminal allylidene groups at the 7- and 12-positions (HCTD-7,12-diallylidene) was generated from norbornadiene via an efficient six-step synthesis. Thermal polymerization at temperatures ranging from 160 to 240° C. yielded a robust cross-linked material with thermal stability up to 485° C. in air, a glass transition temperature of 377° C., and a char yield (600° C.) of 56% in air. Applications include heat resistant composites utilized in the aerospace, electronic, automotive and textile industries.
摘要:
A semiconducting shield composition comprising a polyolefin and acetylene black having at least one of the following properties: (a) a DBP oil adsorption of 150 ml/100 g to 200 ml/100 g; (b) an iodine absorption of 85 mg/g to 105 mg/g; (c) an apparent density of 0.2 g/ml to 0.4 g/ml; (d) a crystallite size along (002) less than 30 Å; and (e) a carbon-carbon bond length along (100) less than 2.42 Å. The semiconducting shield may be incorporated into a semiconducting layer and/or a semiconductor apparatus.
摘要:
Microporous polyolefin and microporous polydicyclopentadiene (polyDCPD) based aerogels and methods for preparing and using the same are provided. The aerogels are produced by forming a polymer gel structure within a solvent from a olefin or dicyclopentadiene monomer 5 via Ring Opening Metathesis Polymerization (ROMP) reactions, followed by supercritical drying to remove the solvent from the aerogel. Other aerogels are prepared by sequentially (1) mixing at least one dicyclopentadiene monomer, at least one solvent at least one catalyst and at least one inorganic and/or organic reinforcing material, (2) gelling the mixture, (3) aging, and (4) supercritical drying. Aerogels provided herein are inexpensive to prepare, possess desirable 10 thermal, mechanical, acoustic, chemical, and physical properties and are hydrophobic. The aerogels provided herein are suitable for use in various applications, including but not limited to thermal and acoustic insulation, radiation shielding, and vibrational damping applications.
摘要:
The disclosed invention relates to a process, comprising: conducting unit operations in at least two process zones in a process microchannel to treat and/or form a non-Newtonian fluid, a different unit operation being conducted in each process zone; and applying an effective amount of shear stress to the non-Newtonian fluid to reduce the viscosity of the non-Newtonian fluid in each process zone, the average shear rate in one process zone differing from the average shear rate in another process zone by a factor of at least about 1.2.
摘要:
The present invention relates to a novel post metallocene-type ligand compound, to a metal compound containing the ligand compound, to a catalytic composition containing the metal compound, and to a method for preparing same, as well as to a method for preparing olefin polymers using the catalytic composition. The present invention provides a catalyst for preparing special polyolefin-based polymers having excellent activity
摘要:
Methods for bonding polymeric substrates to hydroxylated surfaces such as glass are disclosed. The polymeric substrates may be elastomeric substrates such as a natural Or synthetic rubber. The method may comprise applying a compound comprising at least one alkoxy silane moiety and at least one moiety selected from a nitrosoaromatic or a nitrosoaromatic precursor to one of the substrates. The nitrosoaromatic moiety may be a nitrosobenzene. The nitrosoaromatic precursor may be a nitrosobenzene precursor, such as at least one of a quinone dioxime or a quinone oxime. Novel primers and compounds suitable for use in the bonding process are also disclosed.
摘要:
A novel process is used to prepare synthetic rubbers (B) which feature very narrow molecular weight distribution and a correspondingly low value for the polydispersity index. The preparation process encompasses the treatment of a synthetic rubber with ultrasound, where the resultant synthetic rubber (B) has a lower weight-average molecular weight (Mw) than the synthetic rubber (A) used. The resultant synthetic rubbers (B) have excellent suitability for processing via extruder processes or injection-moulding processes.
摘要:
A novel series of copolymers and terpolymers, usefull as base oils for synthetic lubricants, are produced by polymerization of ethylene, an alpha-olefin, and optionally a third monomer comprising an alpha-olefin of 3 to 20 carbon atoms, in the presence of a combination catalyst comprising a compound of a transition metal of Group IVb of the Periodic Table and an aluminoxane. The copolymer or terpolymer may be further processed by thermal cracking to yield novel cracked polymers, and the cracked polymers may be hydrogenated. The copolymers or terpolymers may also be hydroisomerized. All the polymers are useful as base oils for lubricating oils and consumer products.
摘要:
A polydiene which is obtainable by anionic polymerization of a diene using a bifunctional Li initiator followed by polymer-like reaction and which contains at least one ethanolamine or oligoetherolamine terminal group of the general structure I ##STR1## in which R.sup.1 denotes alkyl or aryl, Ar denotes aryl, R.sup.2 denotes alkyl or hydrogen, and R.sup.3 denotes aryl, alkyl, or hydrogen and X can assume a value from 1 to 10, and the hydrogenation products thereof.