EP0055035A1
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EP
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Cementitious composition and cementitious product of high flexural strength
Assignee: Imperial Chemical Industries Ltd
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Filing: 1981-11-27
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Granted: —
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Expires: 2001-11-27
Abstract
Abstract A cementitious composition comprising hydraulic cement, not more than 25% of water by weight of the composition, and water soluble or dispersible (co)polymer in a proportion of 1 to 15% by weight of the hydraulic cement in the composition, the cement and (co)polymer being selected such that a test composition comprising 100 parts by weight of cement, 5 parts by weight of (co)polymer, and 16 parts by weight of water when extruded in a capillary rheometer undergoes an increase of at least 25% in shear stress when a ten-fold increase in the shear rate of the test composition from the capillary of the rheometer is effected. Also a cementitious product produced by setting of the composition. The (co)polymer is preferably a partially hydrolysed poly (vinyi acetate). The cernenti- tious product may have a flexural strength in excess of 100 MPa.
Inventors
- 👤 James Derek Birchall
- 👤 Anthony James Howard
- 👤 Kevin Kendall
- 👤 James Hugh Raistrick
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 15:59
CPC Classifications
C; C04; C04B; C04B7/00; C04B7/345; C04B40/00; C04B40/0028; C04B40/005; C04B24/00; C04B24/24; C04B24/26; C04B24/2623; C04B2111/00; C04B2111/00241; C04B2111/00301
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
139 words
A cementitious composition comprising (a) at least one hydraulic cement, (b) water in a proportion of not more than 25% by weight of the composition, and (c) at least one water-soluble or water-dispersible organic polymer or copolymer in a proportion of 1 to 15% by weight of the hydraulic cement in the composition, characterised in that the hydraulic cement and the polymer or copolymer are selected such that a test composition comprising 100 parts by weight of hydraulic cement, 5 parts by weight of the polymer or copolymer, and 16 parts by weight of water when extruded in a capillary rheometer undergoes an increase of at least 25% in shear stress when a ten-fold increase in the shear rate of the test composition is effected when the shear rates as measured are within the range 0.1 to 5 second.
Claim 2
Dependent Claim
139 words
A cementitious composition comprising (a) at least one hydraulic cement, (b) water in a proportion of not more than 25% by weight of the composition, and (c) at least one water-soluble or water-dispersible organic polymer or copolymer in a proportion of 1 to 15% by weight of the hydraulic cement in the composition, characterised in that the hydraulic cement and the polymer or copolymer are selected such that a test composition comprising 100 parts by weight of hydraulic cement, 5 parts by weight of the polymer or copolymer, and 16 parts by weight of water when extruded in a capillary rheometer undergoes an increase of at least 25% in shear stress when a ten-fold increase in the shear rate of the test composition is effected when the shear rates as measured are within the range 0.1 to 5 second.
Claim 3
Dependent Claim
49 words
A cementitious composition as claimed in claim 1 characterised in that the hydraulic cement and polymer or copolymer are selected such that the test composition undergoes an increase of at least 50% in shear stress when a ten-fold increase in the shear rate of the test composition is effected.
Claim 4
Dependent Claim
26 words
A cementitious composition as claimed in claim 1 or claim 2 characterised in that the organic polymer or copolymer is hydrolysed vinyl acetate polymer or copolymer.
Claim 5
Dependent Claim
20 words
A cementitious composition as claimed in claim 3 characterised in that the organic polymer or copolymer is hydrolysed poly(vinyl acetate).
Claim 6
Dependent Claim
29 words
A cementitious composition as claimed in claim 3 or claim 4 characterised in that the degree of hydrolysis of the vinyl acetate polymer or copolymer is at least 50%.
Claim 7
Dependent Claim
22 words
A cementitious composition as claimed in claim 5 characterised in that the degree of hydrolysis is in the range 70% to 90%.
Claim 8
Dependent Claim
36 words
A cementitious composition as claimed in any one of claims 1 to 6 characterised in that the composition contains at least 3% of organic polymer or copolymer by weight of the hydraulic cement in the composition.
Claim 9
Dependent Claim
27 words
A cementitious composition as claimed in any one of-claims 1 to 7' characterised in that the hydraulic cement is an aluminous cement or a calcium silicate cement.
Claim 10
Dependent Claim
27 words
A cementitious composition as claimed in any one of claims 1 to 8 characterised in that the composition contains not more than 18% by weight of water
Claim 11
Dependent Claim
114 words
A cementitious composition as claimed in any one of claims 1 to 9 characterised in that the composition contains particulate aggregate and in that the hydraulic cement and the polymer or copolymer are selected such that a test composition comprising hydraulic cement plus particulate aggregate (in total 100 parts by weight) , 5 parts by weight of the polymer or copolymer, and 16 parts by weight of water when extruded in a capillary rheometer undergoes an increase of at least 25% in shear stress when a ten-fold increase in the shear rate of the test composition is effected when the shear rates as measured are within the range 0.1 to 5 second -1 .
Claim 12
Dependent Claim
20 words
A cementitious product produced by setting of a cementitious composition as claimed in any one of claims 1 to 10.
Claim 13
Dependent Claim
31 words
A cementitious product as claimed in claim 11 characterised in that not more than 2% of the total volume of the product comprises pores having a maximum dimension exceeding 100 microns.
Claim 14
Dependent Claim
31 words
A cementitious product as claimed in claim 12 characterised in that not more than 0.5% of the total volume of the product comprises pores having a maximum dimension exceeding 15 microns.
Claim 15
Dependent Claim
36 words
A cementitious product as claimed in any one of claims 11 to 13 characterised in that the product comprises a proportion of pores which is not more than 3% of the apparent volume of the product.
Claim 16
Dependent Claim
31 words
A cementitious product as claimed in claim 14 characterised in that the product comprises a proportion of pores which is not more than 1% of the apparent volume of the product.
Claim 17
Dependent Claim
17 words
A cementitious product characterised in that said product has a flexural strength of at least 100 MPa.
Claim 18
Dependent Claim
17 words
A cementitious product characterised in that said product has a flexural strength of at least 100 MPa.
Claim 19
Dependent Claim
22 words
A cementitious product as claimed in claim 16 characterised in that said product has a flexural strength of at least 150 MPa.
References Cited (Backward Citations)
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US4070199A
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