 Crosslinkable polyethylene-based composition for rotational molding |
| OF THE INVENTION As indicated above, the present invention relates to a novel crosslinkable ... |
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| Process for preparation of monocyclopentadienyl metal complex compounds and method of use |
| All reference to the Periodic Table of the Elements herein shall refer to the Periodic Table of ... |
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| Titanium(II) or zirconium(II) complexes and addition polymerization catalysts therefrom |
| According to the present invention there are provided metal complexes containing one and only one ... |
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| Method for preparing ethylene copolymer |
| What is claimed is: 1. A method for preparing an ethylene copolymer which comprises the step of ... |
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| Ethylene-aromatic vinyl compound copolymer and method for its production |
| It is an object of the present invention to provide an ethylene-aromatic vinyl compound copolymer ... |
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| Polyvinylidene fluoride weather resistant coating compositions including polymethyl methacrylate |
| OF THE PREFERRED EMODIMENT In the following description, the invention is described in terms of a ... |
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| Composite closure |
| An improved composite plastic closure for bottles and other containers has a plastic cap with a ... |
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| Polypropylene closure with removable liner |
| OF THE INVENTION In the drawings, a compression molded polypropylene closure or cap 5 is shown, ... |
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| Plastic closure with compression molded sealing liner |
| I claim: 1. A plastic closure comprising a base wall, a peripheral skirt, means on said skirt ... |
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Two-part reactive dielectric filler composition
| Details |
Inventors: Groves, James D.; D'Zuro, Deborah Sue Anne;
Assignee: Minnesota Mining and Manufacturing Company (Saint Paul, MN)
Primary Examiner: Czaja; Donald E.
Assistant Examiner: Fletcher; H. H.
Attorney, Agent or Firm: Alexander; Cruzan, Sell; Donald M., Chernivec; Gerald F.
A two-part pourable composition capable of forming a dielectric, thermally stable, hydrolytically stable, moisture insensitive polyurethane gel comprising in a first part an aliphatic or cycloaliphatic isocyanate and an aliphatic/naphthenic hydrocarbon oil, and in a second part a polyalkadiene polyol, a dialkyl organotin catalyst, and the aliphatic/naphthenic oil. The gel is ideally suitable as a filler for communication cable splices since it is substantially inert toward molded polycarbonate connectors conventionally used in such splices. |
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DETAILED DESCRIPTION OF THE INVENTION The encapsulant useful herein can be described, in its cured state, as hydrocarbon-extended or plasticized polyurethane composition.
The polyurethane useful herein is basically formed by the reaction of a hydroxyl-terminated alkadiene polymer or copolymer with specific organic isocyanates.
Organic isocyanates having utility herein for the formation of the dielectric gel of the invention include aliphatic and cycloaliphatic isocyanates having at least two NCO groups per molecule.
Exemplary of such isocyanates are dimer acid diisocyanate, derived from a C.
sub.
36 dibasic acid; isophorone diisocyanate; trimethylhexamethylene diisocyanate; 4,4'-methylene-bis(cyclohexylisocyanate); etc.
, as well as mixtures of such isocyanates.
Hydrocarbon-extended polyurethanes based on aromatic isocyanates are disclosed and claimed in U.
S.
Pat.
Nos.
3,755,241 and 3,714,110.
However, aromatic isocyanates have been ascertained to have an adverse effect on polycarbonates, i.
e.
stress cracking and/or crazing of molded polycarbonate components occurs when such components are contacted with an aromatic-based system.
Furthermore, most aromatic isocyanates are not compatible with the hereinafter defined aliphatic/naphthenic extender oils useful herein, as they tend to provide a moisture sensitive polyurethane and to foam during curing.
The polyalkadiene polyols useful in the invention herein are liquid or quasi-liquid polymers derived, for example, from the polymerization of butadiene, isoprene, or mixtures thereof, or copolymers derived from the random copolymerization of vinyl monomers, e.
g.
styrene and methyl styrene, with compounds such as butadiene.
The preferred polymers and copolymers have, on the average, greater than 2.
0 terminal hydroxyl groups per molecule, e.
g.
at least about 2.
1, and can have as high as about 2.
6, or even 3.
0 terminal hydroxyl groups per molecule.
Further, hydrogenated derivatives of the polyalkadiene polymers, i.
e.
those having about 70 to about 95 percent hydrogenation, which are waxy solids, are also capable of providing useful dielectric gels herein, such materials possessing improved thermal and hydrolytic stability
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Adhesives and Rubbers 
