US3979480A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the polymerization of formaldehyde
Assignee: Societa Italiana Resine SpA SIR
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Filing: 1974-12-16
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Granted: 1976-09-07
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Expires: 1994-12-16
Abstract
Abstract Polyformaldehyde is prepared by feeding anhydrous formaldehyde to a reaction medium containing a liquid organic diluent non-solvent for the polyformaldehyde and non-reactive towards the other constituents of the reaction medium, and containing in a dispersed form a copolymer A-B, wherein A is a polylactonic block of recurring units ##EQU1## B is a polylactamic block of recurring units ##EQU2## wherein PM 1 and PM 2 are linear polymethylene chains having from 2 to 13 and 3 to 13 carbon atoms, respectively.
Inventors
- 👤 Pierino Radici
- 👤 Daniele Colombo
- 👤 Paolo Colombo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 03:08
CPC Classifications
C; C08; C08G; C08G2/00; C08G2/06; C08G2/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
203 words
A method for preparing a polyoxymethylene, comprising the step of supplying anhydrous monomeric formaldehyde to a reaction medium comprising an organic diluent which is a liquid and non-solvent for the polyoxymethylene under the reaction conditions and inert towards the other constituents of the reaction medium, and comprising from 0.001 to 0.5 percent by weight of a catalyst based upon the polyoxymethylene, dispersed in said medium, said catalyst having a molecular weight of from 1,000 to 50,000, containing block A in a proportion of from 1 to 89 weight percent, and consisting of a block copolymer carrying ionic couples on its macromolecular chain, said block copolymer being defined by the general structure A-B in which: A is a polylactonic block consisting of recurring units: ##EQU5## obtainable from at least one monomeric lactone of the general formula: ##EQU6## B is a polylactam block consisting of recurring units: ##EQU7## obtainable from at least one monomeric lactam of the general formula: ##EQU8## wherein PM 1 and PM 2 are polymethylene chains having from 2 to 13 and 3 to 13 carbon atoms, respctively, non-substituted or having at least one hydrogen atom replaced by a radical selected from the group consisting of alkyl, aryl, alkylaryl and cycloalkyl radicals.
Claim 2
Independent Claim
203 words
A method for preparing a polyoxymethylene, comprising the step of supplying anhydrous monomeric formaldehyde to a reaction medium comprising an organic diluent which is a liquid and non-solvent for the polyoxymethylene under the reaction conditions and inert towards the other constituents of the reaction medium, and comprising from 0.001 to 0.5 percent by weight of a catalyst based upon the polyoxymethylene, dispersed in said medium, said catalyst having a molecular weight of from 1,000 to 50,000, containing block A in a proportion of from 1 to 89 weight percent, and consisting of a block copolymer carrying ionic couples on its macromolecular chain, said block copolymer being defined by the general structure A-B in which: A is a polylactonic block consisting of recurring units: ##EQU5## obtainable from at least one monomeric lactone of the general formula: ##EQU6## B is a polylactam block consisting of recurring units: ##EQU7## obtainable from at least one monomeric lactam of the general formula: ##EQU8## wherein PM 1 and PM 2 are polymethylene chains having from 2 to 13 and 3 to 13 carbon atoms, respctively, non-substituted or having at least one hydrogen atom replaced by a radical selected from the group consisting of alkyl, aryl, alkylaryl and cycloalkyl radicals.
Claim 3
Dependent Claim
22 words
The method of claim 1, wherein the said lactone is selected from the group consisting of ε-caprolactone, δ-valerolactone, β-propiolactone, pivalolactone and ω-enanthiolactone.
Claim 4
Dependent Claim
22 words
The method of claim 1, wherein the said lactam is selected from the group consisting of ε-caprolactam, α-pyrrolidone, ω-lauryllactam, α-piperidone and ω-enanthiolactam.
Claim 5
Dependent Claim
20 words
The method of claim 1, wherein the diluent is selected from the group consisting of ethers, hydrocarbons and chlorinated hydrocarbons.
Claim 6
Dependent Claim
31 words
The method of claim 1, wherein the reaction temperature is from -120° up to the temperature of ebullition of the diluent, said diluent having a temperature of ebullition not exceeding 110°C.
Claim 7
Dependent Claim
14 words
The method of claim 1, wherein the reaction temperature is from -30° to 70°C.
Claim 8
Dependent Claim
96 words
The method of claim 1, wherein the block copolymer A-B is obtained by catalytic copolymerization of said lactamic and lactonic monomers at a temperature of from -20°C to 300°C and during a period of from 2 min to 6 hours, the catalyst employed being in a proportion of from 0.1 to 10 moles for 100 moles lactonic and lactamic monomers and being defined by the general formula: ##STR6## wherein Me is selected from the group consisting of the alkali and alkaline earth metals, Z is 1 or 2 and PM 2 is the said polymethylene chain.
Claim 9
Dependent Claim
24 words
The method of claim 6, wherein the block copolymer A-B is obtained by copolymerizing said monomers in a solvent for the forming copolymer A-B.
Claim 10
Dependent Claim
25 words
The method of claim 6, wherein the block copolymer A-B is obtained by copolymerizing said monomers in a diluent non-solvent for the forming copolymer A-B.
Claim 11
Dependent Claim
22 words
The method of claim 1, wherein the said dispersed catalyst is in the form of particles 1 to 300 microns in size.
Claim 12
Dependent Claim
15 words
The method of claim 10, wherein said particles are 1 to 100 microns in size.
References Cited (Backward Citations)
US3555514A
Cited
US3592873A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-07 | 1980-03-08 | 1980-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-07 | 1984-03-08 | 1984-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-07 | 1988-03-08 | 1988-09-07 | $7700.00 | Window Closed / Lapsed |