Acrylic syrup curable to a crosslinked viscoelastomeric material

• US 5,773,485 A
• Filed: 08/23/1995
• Issued: 06/30/1998
• Est. Priority Date: 07/29/1994
• Status: Expired due to Term

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Bennett, Greggory S., Winslow, Louis E., Babu, Gaddam N.
• Primary Examiner(s): Berman, Susan W.
• Application Number:
  US08/522,294
• Time in Patent Office: 1,042 Days
• Field of Search: 522/120, 522/121, 522/904, 522/905, 522/8, 522/12, 522/35, 522/114, 522/125, 526/208, 526/316
• US Class Current: 522/8
• CPC Class Codes: C08F 2/02 Polymerisation in bulk
• CPC Class Codes: C08F 2/48 by ultraviolet or visible light
• CPC Class Codes: C08F 2/50 with sensitising agents
• CPC Class Codes: C08F 265/00 Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00
• CPC Class Codes: C08F 291/00 Macromolecular compounds obtained by polymerising monomers on to macromolecular compounds according to more than one of the groups C08F251/00 - C08F289/00
• CPC Class Codes: C09D 4/06 Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09D159/00 - C09D187/00
• CPC Class Codes: C09J 4/06 Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09J159/00 - C09J187/00
• CPC Class Codes: G03F 7/027 Non-macromolecular photopolymerisable compounds having carbon-to-carbon double bonds, e.g. ethylenic compounds G03F7/075 takes precedence
• CPC Class Codes: Y10S 522/904 Monomer or polymer contains initiating group
• CPC Class Codes: Y10S 522/905 Benzophenone group

Abstract

Solute polymers in solvent monomers form a coatable syrup that can be cured to a viscoelastomeric material when radiation-sensitive hydrogen abstracting groups in either the polymer or one of the monomers are exposed to ultraviolet radiation. The solute polymers can be formed from the solvent monomers.

Claims

1. A syrup curable to a crosslinked viscoelastomeric material comprising:

a) about 65 to 99.9 weight percent of a solvent monomer mixture comprising

1) 95 to 99.9999 parts by weight of at least one free radically-polymerizable ethylenically unsaturated monomer, and

2) 0.0001 to 5 parts by weight of an ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group;

b) about 0.1 to 35 weight percent of a solute polymer comprising

1) 9s to 99.9999 weight percent mer units derived from one or more free radically-polymerizable ethylenically unsaturated monomers, and

2) about 0.001 to 5 weight percent mer units derived from an ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group,

said polymer having a molecular weight of at least 500,000;

c) from 0.01 to 5 parts by weight of a free radically-polymerizable polyethylenically unsaturated monomer selected from the group consisting of acrylate monomers and divinyl monomers; and

d) from 0.0001 to 3 parts by weight of a saturated energy-activated initiator of polymerization;

wherein the parts by weight of said free radically-polymerizable polyethylenically unsaturated monomer and said saturated energy-activated initiator of polymerization are based upon 100 parts by weight of said solvent monomer mixture and said solute polymer.

2. The syrup of claim 1 wherein said at least one free radically-polymerizable ethylenically unsaturated monomer of said monomer mixture comprises a monoethylenically unsaturated monomer homopolymerizable to a polymer having a glass transition temperature of less than about 0°

C.

3. The syrup of claim 2 wherein said at least one free radically-polymerizable ethylenically unsaturated monomer is selected from the group consisting of isooctyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, decyl acrylate, dodecyl acrylate, hexyl acrylate, and butyl acrylate.

4. The syrup of claim 2 wherein said at least one free radically-polymerizable ethylenically unsaturated monomer further comprises a monoethylenically unsaturated monomer homopolymerizable to a polymer having a glass transition temperature of greater than about 50°

C.

5. The syrup of claim 4 wherein said second monoethylenically unsaturated monomer is selected from the group consisting of (meth)acrylic acid, itaconic acid, N,N-dimethylacrylamide, N-octylacrylamide, 2-hydroxyethyl acrylate, N-vinyl pyrrolidone, N-vinyl caprolactam, acrylonitrile, tetrahydrofurfuryl acrylate, and isobornyl acrylate.

6. The syrup of claim 1 wherein said ethylenically unsaturated monomer comprising a radiation sensitive group has the formula ##STR14## wherein R is H or a C₁ to C₃ alkyl group, preferably H or a methyl group;

X is O or NH;

n is 0 or 1;

m is 0 or an integer from 1 to 5;

a, b, and c are independently 0 or 1;

M¹ is CH₂ or SIR¹ R² ;

M² is CR³ R⁴ or SiR¹ R² ;

M³ is O, NH, C(O), C(O)O, C(O)NH, or OC(O)NH;

R¹ and R² are independently H or a C₁ to C₄ alkyl group;

R³ and R⁴ are independently H, an alkyl group having 1 to 14 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an aryl group having 5 to 12 ring atoms, an arenyl group having 6 to 26 carbon and 0 to 3 S, N, and nonperoxidic 0 heteroatoms, or R³ and R⁴ taken together with the carbon to which they are attached form a carbocyclic ring containing 4 to 12 ring atoms;

G is a covalent bond, (CH₂)_d, or (CH₂)_d O where d is an integer from 1 to 4, preferably from 1 to 2;

Z is a radiation-sensitive hydrogen abstracting group having the general formula ##STR15## in which Ar is a substituted arene having 6 to 12 carbon atoms, preferably a benzenetriyl group;

R⁵ is hydrogen, a C₁ to C₁₂ alkyl group, a C₁ to C₁₂ alkoxy group, or a phenyl group; and

R⁶ is a C₁ to C₆ alkyl group, a cycloalkyl group having 3 to 14 carbon atoms, or ##STR16## wherein R⁷ and R⁸ are independently selected from the class consisting of hydrogen, C₁ to C₁₂ alkyl groups, C₁ to C₁₂ alkoxy groups, and phenyl groups, with the proviso that, when R⁵ and R⁷ (or R⁸) are ortho to the carbonyl group of Z, together they can be one of ##STR17##

7. The syrup of claim 1 wherein said syrup comprises 0.001 to 1.0 parts by weight of said saturated energy-activated initiator of polymerization.

8. The syrup of claim 7 wherein said energy is ultraviolet radiation.

9. The syrup of claim 7 wherein said monomer mixture comprises from 0.005 to 3 parts by weight of said ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group.

10. The syrup of claim 1 wherein said syrup comprises from 0.01 to 0.30 parts by weight of said free radically-polymerizable polyethylenically unsaturated monomer.

11. The syrup of claim 1 wherein said syrup is of a coatable viscosity.

12. A process for making a crosslinked viscoelastomeric material comprising the steps;

a) providing a composition comprising

1) a solvent monomer mixture comprising

(a) 100 parts by weight of at least one free radically-polymerizable ethylenically unsaturated monomer, and

(b) 0.0001 to 5 parts by weight of an ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group, and

2) 0.0001 to 3 parts by weight of a saturated energy-activated initiator of polymerization;

b) exposing said composition to energy so as to partially polymerize said monomer mixture in situ to form a coatable syrup containing a polymer of a molecular weight of at least 500,000 and the polymer comprising monomers

     1) (a) and

     1) (b);

c) adding to said syrup;

1) 0 to 3 parts by weight of a saturated energy-activated initiator of polymerization.

2) 0 to 3 parts by weight of an ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group, and

3) 0.01 to 5 parts by weight of a free radically-polymerizable polyethylenically unsaturated monomer selected from the group consisting of acrylate monomers and divinyl monomers; and

d) exposing said syrup to energy that activates said initiator and said hydrogen abstracting group of said ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group so as to form said crosslinked viscoelastomeric material.

13. The process of claim 12 wherein said ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group has the formula ##STR18## wherein R is H or a C₁ to C₃ alkyl group, preferably H or a methyl group;

X is O or NH;

n is O or 1;

m is 0 or an integer from 1 to 5;

a, b, and c are independently 0 or 1;

M¹ is CH₂ or SiR¹ R² ;

M² is CR³ R⁴ or SiR¹ R² ;

M³ is O, NH, C(O), C(O)O, C(O)NH, or OC(O)NH;

R¹ and R² are independently H or a C₁ to C₄ alkyl group;

R³ and R⁴ are independently H, an alkyl group having 1 to 14 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an aryl group having 5 to 12 ring atoms, an arenyl group having 6 to 26 carbon and 0 to 3 S, N, and nonperoxidic O heteroatoms, or R³ and R⁴ taken together with the carbon to which they are attached form a carbocyclic ring containing 4 to 12 ring atoms;

G is a covalent bond, (CH₂)_d, or (CH₂)_d O where d is an integer from 1 to 4, preferably from 1 to 2;

Z is a radiation-sensitive hydrogen abstracting group having the general formula ##STR19## in which Ar is a substituted arene group having 6 to 12 carbon atoms;

R⁵ is hydrogen, a C₁ to C₁₂ alkyl group, a C₁ to C₁₂ alkoxy group, or a phenyl group; and

R⁶ is a C₁ to C₆ alkyl group, a cycloalkyl group having 3 to 14 carbon atoms, or ##STR20## wherein R⁷ and R⁸ are independently selected from the class consisting of hydrogen, C₁ to C₁₂ alkyl groups, C₁ to C₁₂ alkoxy groups, and phenyl groups, with the proviso that, when R⁵ and R⁷ (or R⁸) are ortho to the carbonyl group of Z, together they can be one of ##STR21##

14. A syrup curable to a crosslinked viscoelastomeric material comprising:

a) about 65 to 99.9 weight percent of a solvent monomer mixture comprising

1) 95 to 99.9999 parts by weight of at least one free radically-polymerizable ethylenically unsaturated monomer, and

2) 0.0001 to 5 parts by weight of an ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group;

b) about 0.1 to 35 weight percent of a solute polymer comprising

1) 95 to 99,9999 weight percent mer units derived from one or more free radically-polymerizable ethylenically unsaturated monomers, and

2) about 0.001 to 5 weight percent mer units derived from an ethylenically unsaturated monomer comprising a radiation-sensitive hydrogen abstracting group,

said polymer having a molecular weight of at least 500,000;

c) from 0.01 to 5 parts by weight of a free radically-polymerizable polyethylenically unsaturated monomer selected from the group consisting of ethylene glycol diacrylate, propyleneglycol dimethacrylate, trimethylolpropane triacrylate, 1.6-hexamethylenedioldiacrylate, pentaerythritol di-, tri-, and tetraacrylate, 1,12-dodecanediol diacrylate, allyl methacrylate, 2-allyloxycarbonylamidoethyl methacrylate, 2-allylaminoethyl acrylate, allyl 2-acrylamido-2,2-dimethylacetate, and divinylbenzene; and

d) from 0.0001 to 3 parts by weight of a saturated energy-activated initiator of polymerization;

wherein the parts by weight of said free radically-polymerizable polyethylenically unsaturated monomer and said saturated energy-activated initiator of polymerization are based upon 100 parts by weight of said solvent monomer mixture and said solute polymer.