Cement admixture

A cement admixture and addition technology, applied in the field of cement admixtures, can solve the problems of not being able to provide high-purity copolymers, achieve excellent cement dispersion performance and water-reducing performance, and improve operating efficiency.

Inactive Publication Date: 2008-03-19
NIPPON SHOKUBAI CO LTD
View PDF18 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method cannot provide high-purity copolymers while suppressing side reactions

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Cement admixture
  • Cement admixture
  • Cement admixture

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0140] A 20 mol addition compound of ethylene oxide to vinyl ether (hereinafter referred to as VE-20) was synthesized from diethylene glycol monovinyl ether (DEGV) produced by CHEMIWAY Maruzen Petrochemical Co., Ltd. 163.4 g of a 65% by weight aqueous solution of VE-20 was charged into a container equipped with a thermostat, a stirring blade, and a nitrogen gas introduction port, and the temperature of the solution was set at 29°C. Under the condition of 100ml / min nitrogen flow into the container, 20.3g of 70% by weight aqueous acrylic acid was added dropwise within 1.5 hours, and 21.2g of 4mol% / monomer hydrogen peroxide solution and 44.9% were added dropwise within 1.75 hours. g An aqueous solution in which 1.5 mol% / monomer of β-mercaptopropionic acid and 1 mol% / monomer of L-ascorbic acid are dissolved. After 1.75 hours from the start, the solution was aged for 30 minutes. The reaction temperature during the reaction was controlled at 27 to 30°C.

[0141]The solid content o...

Embodiment 2

[0143] [Production of polycarboxylate polymer (B-1)]

[0144] 995 parts of distilled water were charged into a reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen gas introduction port, and a condenser, and the temperature was raised to 70°C. Then, dropwise added by mixing 1067 parts of monomer (b-1) shown in Table 1, 283 parts of methacrylic acid, 41.2 parts of 48% aqueous sodium hydroxide solution, 20 parts of 3-mercaptopropionic acid and 354 parts 240 parts of 6.5% ammonium persulfate aqueous solution was added dropwise within 6 hours. After the dropwise addition was complete, the reaction mixture was kept at 70°C for 1 hour. After cooling the solution, 30% aqueous sodium hydroxide solution was added to adjust the pH to 7 to obtain an aqueous solution (solid) of a polycarboxylic acid-based polymer (B-1) having a weight average molecular weight of 14,000 in terms of polyethylene glycol measured by GPC. Ingredient concentration 45% by weight).

[...

Embodiment 3

[0148] [Production of polycarboxylate polymer (B-2)]

[0149] 695.5 parts of distilled water were charged into a reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen gas introduction port, and a condenser, and the temperature was raised to 70°C. Then, dropwise added by mixing 1244.6 parts of monomer (b-1) shown in Table 1, 330.4 parts of methacrylic acid, 76.1 parts of 30% aqueous sodium hydroxide solution, 34.6 parts of 3-mercaptopropionic acid and 368.6 parts Parts of distilled water prepared solution, 240 parts of 2.4% hydrogen peroxide aqueous solution was added dropwise within 6 hours, and 245 parts of 3.1% L-ascorbic acid aqueous solution was added dropwise within 6 hours. After the dropwise addition was complete, the reaction mixture was kept at 70°C for 1 hour. After cooling the solution, 30% aqueous sodium hydroxide solution was added to adjust the pH to 7 to obtain an aqueous solution (solid) of a polycarboxylic acid-based polymer (B-2) havi...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The present invention aims at providing a cement admixture having superior water-reducing performance, along with no decrease in slump and slump flow caused by decrease in fluidity of a cement composition over time. A cement admixture is to be provided, which cement admixture comprises two or more members of polycarboxylic acid-based polymers, wherein said cement admixture comprises at least one polycarboxylic acid-based polymer (A) having a constitutional unit represented by the following formula (1): wherein R1 and R2 independently represent a hydrogen atom, an alkyl group with carbon atoms of 1 to 30, an alkenyl group with carbon atoms of 1 to 30, an aryl group with carbon atoms of 6 to 12; A represents an alkylene group with carbon atoms of 1 to 30 or an arylene group with carbon atoms of 6 to 12; a is 0 or 1; OR3 represents an oxyalkylene group with carbon atoms of 2 to 18, wherein each OR3 may be the same or different each other, provided that when OR3 is in a mixed form of two or more members, each OR3 may be added in a block or random form; R4 represents a hydrogen atom or a hydrocarbon group with carbon atoms of 1 to 30; and m represents an average mole number of oxyalkylene groups added and is in the range of 1 to 300; and at least one polycarboxylic acid-based polymer (B) having a constitutional unit represented by the following formula (2): wherein R5 and R6 independently represent a hydrogen atom, a methyl group; x is an integer in the range of 0 to 2 and y is 0 or 1, provided that x and y are not 0 at the same time; OR7 represents an oxyalkylene group with carbon atoms of 2 to 18, wherein each OR7 may be the same or different each other, provided that when OR7 is in a mixed form of two or more members, each OR7 may be added in a block or random form; R8 represents a hydrogen atom or a hydrocarbon group with carbon atoms of 1 to 30; and n represents an average mole number of oxyalkylene groups added and is in the range of 1 to 300.

Description

technical field [0001] The present invention relates to cement admixture. More specifically, the present invention relates to cement admixtures containing two or more polycarboxylic acid-based polymer components having specific constituent units. Background technique [0002] Cement admixtures containing polycarboxylic acid-based polymers have been widely used in cement compositions such as cement paste, mortar, concrete, etc., and are currently irreplaceable materials for structures such as civil engineering and buildings constructed of cement compositions. This cement admixture is used as a water reducing agent and improves the strength or durability of hardened materials by improving the fluidity of cement compositions and reducing the water content of cement compositions. As such a water reducer, a polycarboxylate-based water reducer having a polycarboxylate-based polymer as a main component achieves higher water-reducing performance than conventional naphthalene-based ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C04B24/26C08F290/06C08L33/14C04B103/32
CPCC04B2103/308C04B2103/302C04B40/0039C08F290/06C08L33/14C04B24/2605C08F290/00C08L53/005C08L53/00C04B28/02C08L2666/04C08L2666/02C04B24/2647
Inventor 山崎博枚田健山下明彦
Owner NIPPON SHOKUBAI CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products