Patent EP0335499A2 successfully refreshed from Google Patents.
EP0335499A2
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EP
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Method of producing thermoplastic elastomers having alternate crystalline structure for use as binders in high-energy compositions
Assignee: ATK Launch Systems LLC
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Filing: 1989-02-24
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Granted: —
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Expires: 2009-02-24
Abstract
Abstract A method is provided for synthesizing block polymers which are thermoplastic elastomers. The thermoplastic elastomers are useful as binders in high-energy compositions, such as propellants, explosives, gasifiers or the like. The block polymers have both (A) and (B) blocks; the A blocks being crystalline at temperatures below 60°C and the B blocks being amorphous at temperatures above -20°C. Both the A and B blocks are polyethers formed from monomers of oxetanes and/or tetrahydrofuran. To prepare the block polymers, the (A) and (B) blocks are separately prepared and separately end-capped by reacting each block with a diisocyanate in which one of the isocyanate moieties is substantially more reactive with the terminal hydroxyl groups of the blocks than the other. Reaction of the more reactive isocyanate moiety with the terminal hydroxyl groups leaves the other isocyanate group free. The end-capped (A) and (B) blocks are mixed and reacted with a short linking compound which has two isocyanate-reactive groups.
Inventors
- 👤 Robert Budge Wardle
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 06:29
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/74; C08G18/76; C08G18/7614; C08G18/7621; C08G18/08; C08G18/10; C08G18/12; C08G18/28; C08G18/40; C08G18/48; C08G18/4854; C08G18/4858; C08G18/50; C08G18/5003; C08G18/5021; C08G18/67; C08G18/6795; C08G18/75; C08G18/751; C08G18/752; C08G18/753; C08G18/755; C08G2250/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
217 words
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°C and said B block(s) is amorphous at temperatures above about -20°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 hydroxyl terminated A blocks which are crystalline at temperatures below about 60°C and separately providing hydroxyl terminated B blocks which are amorphous at temperatures above about -20°C, end-capping said A blocks and said B blocks by separately reacting each of said A blocks and B blocks with a diisocyanate in which one isocyanate moiety is at least about five times as reactive with the terminal hydroxyl groups of each of the blocks as the other isocyanate moiety, whereby the more reactive isocyanate moiety tends to react with terminal hydroxyl groups of the blocks, leaving the less reactive isocyanate moiety free and unreacted, mixing said end-capped A blocks and said end-capped B blocks together at approximately the stoichiometric ratios that they are intended to be present in the thermoplastic elastomer, and reacting said mixture with a linking compound having two isocyanate-reactive groups which are sufficiently unhindered to react with the free isocyanate groups of said end-capped polymer.
Claim 2
Independent Claim
217 words
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°C and said B block(s) is amorphous at temperatures above about -20°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 hydroxyl terminated A blocks which are crystalline at temperatures below about 60°C and separately providing hydroxyl terminated B blocks which are amorphous at temperatures above about -20°C, end-capping said A blocks and said B blocks by separately reacting each of said A blocks and B blocks with a diisocyanate in which one isocyanate moiety is at least about five times as reactive with the terminal hydroxyl groups of each of the blocks as the other isocyanate moiety, whereby the more reactive isocyanate moiety tends to react with terminal hydroxyl groups of the blocks, leaving the less reactive isocyanate moiety free and unreacted, mixing said end-capped A blocks and said end-capped B blocks together at approximately the stoichiometric ratios that they are intended to be present in the thermoplastic elastomer, and reacting said mixture with a linking compound having two isocyanate-reactive groups which are sufficiently unhindered to react with the free isocyanate groups of said end-capped polymer.
Claim 3
Dependent Claim
75 words
The method according to Claim 1 wherein said oxetane monomers have the general formula: wherein the R groups are the same or different and are selected from moieties having the general formulae: -(CH₂) n X, where n is 0-10 and X is selected from the group consisting of -H, -NO₂, -CN, -Cl, F, -O-alkyl, -OH, -I, -ONO₂, -N(NO₂)-alkyl, -C≡CH, -Br, -CH=CH(H or alkyl), -O-CO-(H or alkyl), -CO₂-(H or alkyl), -N(H or alkyl)₂, -O-(CH₂)₁₋₅-O-(CH₂)₀₋₈-CH₃, and -N₃.
Claim 4
Dependent Claim
78 words
A method according to Claim 1 or Claim 2 wherein said THF monomers have the general formula: wherein the R groups are the same or different and are selected from moieties having the general formulae: -(CH₂) n X, where n is 0-10 and X is selected from the group consisting of -H, -NO₂, -CN, -Cl, F, -O-alkyl, -OH, -I, -ONO₂, -N(NO₂)-alkyl, -C≡CH, -Br, -CH=CH(H or alkyl), -O-CO-(H or alkyl), -CO₂-(H or alkyl), -N(H or alkyl)₂, -O-(CH₂)₁₋₅-O-(CH₂)₀₋₈-CH₃, and -N₃.
Claim 5
Independent Claim
35 words
A method according to any preceding claim wherein said B block(s) has a molecular weight of between 5000 and 50,000 and each of said A blocks has a molecular weight of between 3000 and 12,500.
Claim 6
Independent Claim
35 words
A method according to any preceding claim wherein said A blocks together have a molecular weight between 1/3 and 1 times the molecular weight of said B block or total weight of said B blocks.
Claim 7
Dependent Claim
22 words
A method according to Claim 1 wherein said A block is selected from the group consisting of poly(3,3-bis(ethoxymethyl)oxetane), poly(3,3-bis(methoxymethyl)oxetane), poly(3,3-bis(fluromethyl)oxetane), and poly(3,3-bis(azidomethyl)oxetane).
Claim 8
Dependent Claim
34 words
A method according to Claim 1 wherein said B block is selected from poly(3-azidomethyl-3-methyloxetane), (3-azidomethyl-3-methyloxetane)/3,3-bis(azidomethyl)oxetane copolymer, tetrahydrofuran/3,3-bis(azidomethyl)oxetane copolymer, tetrahydrofuran/3-azidomethyl-3-methyloxetane copolymer, tetrahydrofuran/3-octoxymethyl-3-methyloxetane copolymer, tetrahydrofuran/3,3-bis(methyoxyethoxymethyl)oxetane copolymer, tetrahydrofuran/3,3-bis(ethoxymethyl)oxetane copolymer, tetrahydrofuran/3,3-bis(methoxymethyl)oxetane copolymer, tetrahydrofuran/3,3-bis(fluromethyl)oxetane copolymer, poly(3-nitratomethyl-3-methyloxetane), and 3,3-bis(azidomethyl)oxetane/3-nitratomethyl-3-methyloxetane) copolymer.
Claim 9
Dependent Claim
37 words
A method according to Claim 1 wherein said oxetane monomers are selected from the group consisting of: 3,3-bis(ethoxymethyl)oxetane, 3,3-bis(chloromethyl)oxetane, 3,3-bis(methoxymethyl)oxetane, 3,3-bis(fluromethyl)oxetane, 3-hydroxymethyl-3-methyloxetane, 3,3-bis(acetoxymethyl)oxetane, 3,3-bis(hydroxymethyl)oxetane, 3-octoxymethyl-3-methyloxetane, 3,3-bis(methoxyethoxymethyl)oxetane, 3-chloromethyl-3-methyloxetane, 3-azidomethyl-3-methyloxetane, 3-3-bis(iodomethyl)oxetane, 3-iodomethyl-3-methyloxetane, 3-propynomethylmethyloxetane, 3,3-bis(nitratomethyl)oxetane, 3-nitratomethyl-3-methyloxetane, 3,3-bis(methylnitraminomethyl)oxetane, 3-methylnitraminomethyl-3-methyloxetane, and 3,3-bis(azidomethyl)oxetane.
Claim 10
Independent Claim
13 words
A method according to any preceding claim wherein said diisocyanate is toluene diisocyanate.
Claim 11
Independent Claim
17 words
A method according to any one of Claims 1 to 8, wherein said diisocyanate is isophorone diisocyanate.
Claim 12
Independent Claim
28 words
A method according to any preceding claim wherein said end-capping reaction and said reaction with said linking compound are each conducted in the presence of a urethane catalyst.
Claim 13
Independent Claim
47 words
A method according to any preceding Claim wherein each of said A blocks and said B blocks are difunctional and said linking compound is provided at about a 0.4 to 0.6 molar ratio relative to total A and B blocks, whereby an (AB) n polymer is produced.
Claim 14
Independent Claim
37 words
A method according to any preceding Claim wherein in said end-capping reaction, when either of said blocks has a pair of terminal hydroxyl groups, said diisocyanate is provided at between a 1.75 and a 2.2 molar ratio.
References Cited (Backward Citations)
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