US4376852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing cellulose pulp filler for thermosetting resin molding powders
Assignee: Mo och Domsjo AB
•
Filing: 1981-05-01
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Granted: 1983-03-15
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Expires: 2001-05-01
Abstract
Abstract A process is provided for preparing a graft polymermodified cellulose pulp filler from cellulose sulfite pulp having an R 18 value greater than 80%, which comprises adding to the pulp a redox initiator; washing the pulp with water having a pH below 5 in an amount sufficient to adjust the redox initiator cation content to within the range from about 5 to about 1000 ppm of cellulose sulfite pulp; adding hydrogen peroxide in an amount to provide within the range from about 0.1% to about 4% H 2 O 2 by weight of the sulfite pulp; and then reacting the pulp with at least one monomer having the formula: ##STR1## in which: R 1 is hydrogen or methyl; and R 2 is selected from the group consisting of nitrilo --CN, ##STR2## and COOR 3 groups, wherein R 3 is selected from the group consisting of methyl, ethyl, n-butyl, isobutyl and 2-ethylhexyl; at a temperature at which grafting of the monomer onto the cellulose polymer molecule proceeds but below about 70° C. for a time less than twelve hours under an inert atmosphere in a grafting ratio within the range from about 1 to about 40% and an average degree of polymerization within the range from about 20 to about 4000; and then recovering the graft polymer-modified cellulose sulfite pulp. The resulting cellulose pulp is adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity.
Inventors
- 👤 Sven G. Lindenfors
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:55
CPC Classifications
C; C08; C08L; C08L61/00; C08L61/04; C08L61/06; C08F; C08F251/00; C08F251/02; C08L61/20; C08L61/22; C08L61/24
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
225 words
A process for preparing a graft polymer-modified cellulose pulp filler from cellulose sulfite pulp having an R 18 value greater than 80%, which comprises adding to the pulp a redox initiator; washing the pulp with water having a pH below 5 in an amount sufficient to adjust the redox initiator cation content to within the range from about 5 to about 1000 ppm of cellulose sulfite pulp; adding hydrogen peroxide in an amount to provide within the range from about 0.1% to about 4% H 2 O 2 by weight of the sulfite pulp; and then reacting the pulp with at least one monomer having the formula: ##STR10## in which: R 1 is hydrogen or methyl; and R 2 is selected from the group consisting of nitrilo--CN, ##STR11## and COOR 3 groups, wherein R 3 is selected from the group consisting of methyl, ethyl, n-butyl, isobutyl and 2-ethylhexyl; at a temperature at which grafting of the monomer onto the cellulose polymer molecule proceeds but below about 70° C. for a time less than twelve hours under an inert atmosphere, the monomer being added in an amount sufficient to provide a grafting ratio within the range from about 1 to about 40% and an average degree of polymerization within the range from about 20 to about 4000; and then recovering the graft polymer-modified cellulose sulfite pulp.
Claim 2
Dependent Claim
225 words
A process for preparing a graft polymer-modified cellulose pulp filler from cellulose sulfite pulp having an R 18 value greater than 80%, which comprises adding to the pulp a redox initiator; washing the pulp with water having a pH below 5 in an amount sufficient to adjust the redox initiator cation content to within the range from about 5 to about 1000 ppm of cellulose sulfite pulp; adding hydrogen peroxide in an amount to provide within the range from about 0.1% to about 4% H 2 O 2 by weight of the sulfite pulp; and then reacting the pulp with at least one monomer having the formula: ##STR10## in which: R 1 is hydrogen or methyl; and R 2 is selected from the group consisting of nitrilo--CN, ##STR11## and COOR 3 groups, wherein R 3 is selected from the group consisting of methyl, ethyl, n-butyl, isobutyl and 2-ethylhexyl; at a temperature at which grafting of the monomer onto the cellulose polymer molecule proceeds but below about 70° C. for a time less than twelve hours under an inert atmosphere, the monomer being added in an amount sufficient to provide a grafting ratio within the range from about 1 to about 40% and an average degree of polymerization within the range from about 20 to about 4000; and then recovering the graft polymer-modified cellulose sulfite pulp.
Claim 3
Dependent Claim
12 words
A process according to claim 1 in which the monomer is acrylamide.
Claim 4
Dependent Claim
12 words
A process according to claim 1 in which the monomer is acrylonitrile.
Claim 5
Dependent Claim
13 words
A process according to claim 1 in which the monomer is methyl acrylate.
Claim 6
Dependent Claim
13 words
A process according to claim 1 in which the monomer is ethylhexyl acrylate.
Claim 7
Dependent Claim
20 words
A process according to claim 1 in which the cellulose sulfite pulp is prepared by a one-stage sulfite digestion process.
Claim 8
Dependent Claim
20 words
A process according to claim 1 in which the cellulose sulfite pulp is prepared by a two-stage sulfite digestion process.
Claim 9
Dependent Claim
21 words
A process according to claim 1 in which the temperature is within the range from about 10° to about 50° C.
Claim 10
Dependent Claim
19 words
A process according to claim 1 in which the redox initiator comprises Fe 2+ /H 2 O 2 .
Claim 11
Dependent Claim
19 words
A process according to claim 1 in which the redox initiator comprises Ce 4+ /H 2 O 2 .
Claim 12
Dependent Claim
19 words
A process according to claim 1 in which the redox initiator comprises Mn 3+ /H 2 O 2 .
Claim 13
Dependent Claim
29 words
A process according to claim 1 which comprises bleaching the graft polymer-modified pulp with a chlorine-containing bleaching agent selected from the group consisting of chlorine, chlorine dioxide and hypochlorite.
Claim 14
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 1.
Claim 15
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 2.
Claim 16
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 3.
Claim 17
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 4.
Claim 18
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 5.
Claim 19
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 6.
Claim 20
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 7.
Claim 21
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 8.
Claim 22
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 9.
Claim 23
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 10.
Claim 24
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 11.
Claim 25
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehye, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 1.
Claim 26
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 2.
Claim 27
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 3.
Claim 28
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 4.
Claim 29
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 5.
Claim 30
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 6.
Claim 31
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 7.
Claim 32
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 8.
Claim 33
Dependent Claim
36 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite pulp prepared according to the process of claim 9.
Claim 34
Dependent Claim
42 words
Cellulose sulfite pulp adapted for use as a filler for thermosetting resins, imparting to the resins increased impact strength and structural strength, improved resistance to heat distortion and shrinkage, and decreased water absorptivity, and prepared according to the process of claim 10.
Claim 35
Dependent Claim
35 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite prepared according to the process of claim 11.
Claim 36
Dependent Claim
35 words
A molding powder comprising a thermosetting resin selected from the group consisting of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and unsaturated polyester and, as a filler, a graft-polymer-modified cellulose sulfite prepared according to the process of claim 12.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-14 | 1986-09-13 | 1987-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-14 | 1990-09-13 | 1991-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-14 | 1994-09-13 | 1995-03-15 | $7700.00 | Window Closed / Lapsed |