KR20140073291A

KR20140073291A - Cellulose Ether Additive and Cement Mortar Composition for Extrusion Molding Containing the Same

Info

Publication number: KR20140073291A
Application number: KR1020120141363A
Authority: KR
Inventors: 김두호; 강민석
Original assignee: 삼성정밀화학 주식회사
Priority date: 2012-12-06
Filing date: 2012-12-06
Publication date: 2014-06-16

Abstract

The present invention relates to a cellulose ether additive which can be used for mortar for cement-based extrusion molding, and a mortar composition for cement-based extrusion molding comprising the same. The cellulose ether additive according to the present invention comprises hydroxyalkylcellulose By using such additives, it is possible to delay the setting time of the extruded mortar, thereby prolonging the acceleration coupling time of the cement mortar through securing the production time, and maintaining the moldability and clean surface.

Description

Description: TECHNICAL FIELD The present invention relates to a cellulose ether additive and a mortar composition for cement mortar extrusion molding,

The present invention relates to a cellulose ether additive and a mortar composition for cement extrusion molding comprising the same. More particularly, the present invention relates to a cellulose ether additive which can delay the setting time of the mortar for extrusion molding, thereby increasing the accelerated bonding time of the cement mortar by securing the production time and maintaining the moldability and clean surface, and a cement- To a mortar composition for extrusion molding.

Extrusion panels used in interior and exterior materials of buildings are widely used as exterior materials of buildings, interior wall materials, window panels, soundproof walls, underground double walls, etc. with excellent impact resistance, peeling resistance and stain resistance.

In addition, due to the need for construction materials and high-durability building materials due to the increase in the number of buildings and the increase in size of buildings, cement extrusion panels, which can be applied to industrialized building materials, have been in demand for apartments, high-rise offices, This trend is increasing.

Also, as the amount of CO ₂ generated in the cement is reduced and resource recycling is carried out throughout the industry, the cement extruded mortar, which has been introduced into the extruder to separate the materials and cause defects such as cracking and peeling, is reused or waste wollastons and waste paper Cost reduction of materials used is becoming an important issue.

As an important performance factor required for cement-based extrusion panels, cellulose ether is used as an additive in order to improve formability, lubricity, and water retention. Cross-linking strength between cellulose ether and cement mortar is enhanced, Which is characterized by high moldability and smooth surface.

As related art related thereto, Publication No. 10-2009-0080333; And Publication No. 10-2006-0081551.

In the above-mentioned Document No. 10-2009-0080333 (cement mortar additive for extrusion molding, cement mortar for extrusion molding containing the additive, and method for producing cement mortar for extrusion molding using the additive), hydroxyethyl methylcellulose HEMC) and hydroxypropylmethylcellulose (HPMC) with 10 to 60% by weight of hydroxyethylcellulose while a defoaming agent is added to improve the green density of the cement panel for extrusion molding.

However, the above document fails to provide in-depth solutions to the problems caused by dewatering, tearing due to coagulation hardening phenomenon, and separation of materials under a high temperature environment by retaining the mortar for a long time in the extruder for changing the actual size. In addition, since the cement panel for extrusion molding is produced by removing the air inside the mortar through the vacuum extrusion process at the time of extrusion, there is a problem that the bubble reduction effect due to the addition of hydroxyethyl cellulose is insufficient in relation to the actual production process .

In another document, No. 10-2006-0081551 (non-slip extrusion-molded concrete panel and its manufacturing method), sand, plasticizer, chemical fiber and wollastonite are added to a mixed raw material composed of cement, silica powder, cellulose pulp and silica fume, And the concrete panel composition of the non-slip surface extrusion molding is a technical feature.

However, mortar additives for cement-based extrusion molding containing cellulose ether have problems in the formability of the extruded product due to rapid temperature rise in the summer and high temperature characteristics due to the temperature load inside the extruder, resulting in rapid moisture evaporation of the extruded mortar, .

Accordingly, the present inventors have studied a method for improving defects such as tearing and cracking due to condensation and moisture evaporation that occurred during the standard changing process at the time of extrusion of cement, and found that a hydroxyalkylalkylcellulose having a specific degree of substitution And hydroxyalkylcellulose having a specific degree of substitution is added to the mortar for cement-based extrusion molding, the above problems can be solved and the present invention has been completed.

The object of the present invention is to provide a mortar for cement-based extrusion molding capable of prolonging the accelerated bonding time of the cement mortar by maintaining the production time by delaying the curing time of the mortar for extrusion molding, And to provide a cellulose ether additive which can be used in the present invention.

Another problem to be solved by the present invention is to provide a cellulose ether additive capable of maintaining an excellent moldability and a clean surface while extending the accelerated bonding time of the cement mortar by securing the production time by delaying the coagulation time of the mortar for extrusion molding To provide a mortar composition for cement mortar extrusion molding.

In order to solve the above problems, the present invention provides a cellulose ether additive comprising a hydroxyalkyl alkyl cellulose mixed with a hydroxyalkyl cellulose.

In the cellulose ether additive according to the present invention, it is preferable that the hydroxyalkylcellulose is mixed in an amount of 10 to 30% by weight based on the total weight of the cellulosic ether additive.

The hydroxyalkylcellulose has a degree of substitution (DS) of 0.20 to 2.0, a degree of substitution (MS) of hydroxyalkyl group of 0.04 to 1.0, and a hydroxyalkyl group degree of substitution (MS) of the hydroxyalkylcellulose 1 to 5 is preferable.

The hydroxyalkylalkylcellulose is preferably hydroxypropylmethylcellulose or hydroxyethylmethylcellulose, and the hydroxyalkylcellulose is preferably hydroxyethylcellulose.

In order to solve the above-mentioned problems, the present invention provides a mortar composition for cement mortar extrusion molding, which comprises a cellulose ether additive in which a hydroxyalkyl alkyl cellulose is mixed with a hydroxyalkyl cellulose, in a mortar composition for cement mortar extrusion molding.

In the cement mortar composition for extrusion molding according to the present invention, the cellulose ether additive is preferably contained in an amount of 0.1 to 5% by weight based on the total weight of the mortar composition.

Also, the mortar composition for cement mortar extrusion molding according to the present invention comprises 40 to 60% by weight of cement, 20 to 40% by weight of silica sand, 10 to 40 parts by weight of water are added to 100 parts by weight of a dry mixture containing 5 to 15% by weight of polypropylene fiber, 0.1 to 3% by weight of polypropylene fiber, 0.1 to 5% by weight of cellulose ether additive and 0.1 to 10% .

The mortar composition for cement mortar extrusion molding including the cellulose ether additive according to the present invention has the following effects.

First, hydroxyalkylcellulose having a specific degree of substitution is incorporated into hydroxyalkylalkylcellulose having a specific degree of substitution, and cracks and tears due to condensation and moisture evaporation occurring in the process of changing specifications during cement extrusion Can be prevented.

Second, the mortar for cement-based extrusion molding not containing hydroxyalkyl cellulose was cracked at the retention time of 60 minutes in the extruder, but the mortar containing the hydroxyalkylcellulose having a specific degree of substitution provides an extruded mortar having a smooth surface .

Third, in the case of containing hydroxyalkyl cellulose having a specific degree of substitution with cellulose ether, although the cellulose ether is generally increased by 100 to 200% in order to ensure extrusion properties at high temperatures, provision of a product having a clean surface This is possible.

FIG. 1 is a graph showing delay in setting time of extruded mortar prepared from Examples and Comparative Examples according to the present invention.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a mortar composition for cement extrusion molding, which is widely used for interior wall materials for buildings, exterior wall materials, whiskers, soundproof panels and the like. Particularly, in the process of replacing the extrusion dies for changing the specifications of the cement extrusion molding panel in the field (changing the usage standard), the dewatering, condensation and curing phenomena of the mortar left in the extruder And a cellulosic ether additive containing hydroxyalkylcellulose having a specific degree of substitution so as to prevent the deterioration of material separation and tearing of the extruded mortar due to the lack of water retention and lubrication at the end and to delay the setting time of the extruded mortar The present invention relates to a mortar composition for cement mortar extrusion molding, which is capable of maintaining a good moldability and a clean surface while prolonging the accelerated bonding time of the cement mortar through securing the production time.

According to one embodiment of the present invention, the present invention is a cellulose ether additive which can be used in mortar for cement-based extrusion molding in which hydroxyalkylcellulose is mixed with hydroxyalkylcellulose.

The hydroxyalkylcellulose used in the cellulose ether additive according to the present invention is mixed in an amount of 10 to 30% by weight based on the total weight of the cellulose ether additive.

When the amount of the hydroxyalkylcellulose is less than 10% by weight, condensation problems may occur due to dehydration of the mortar, and when the amount exceeds 30% by weight, there is a problem of pressure rise and condensation delay during extrusion, I can not.

The most preferred hydroxyalkylalkylcellulose is hydroxypropylmethylcellulose or hydroxyethylmethylcellulose, and the hydroxyalkylcellulose is most preferably hydroxyethylcellulose.

In the cellulose ether additive, the hydroxyalkyl alkyl cellulose has an alkyl group degree of substitution (DS) of 0.20 to 2.0, a hydroxyalkyl group degree of substitution (MS) of 0.04 to 1.0, and the hydroxyalkyl cellulose has a hydroxyalkyl group substitution degree (MS) of 1 to 5 is preferable.

By using cellulose ether having the above specific substitution degree as an additive, it is possible to reduce the amount of air mixed in the mixing process of the cement mortar for extrusion molding, to reduce the occurrence of bubbles, and to have excellent water retention and lubricity.

In the hydroxyalkyl cellulose, the viscosity is preferably 50,000 to 100,000 cps under the conditions of 20 ° C and 20 rpm when measured with a Brookfield viscometer on the basis of 2% solution, and the hydroxyalkylcellulose preferably has a Brookfield viscosity When measured by a viscometer, it is preferably 30,000 to 40,000 cps under conditions of 20 ° C and 20 rpm.

According to another embodiment of the present invention, there is provided a mortar composition for cement mortar extrusion molding, which comprises a mortar composition for cement mortar extrusion molding, which comprises a cellulose ether additive in which a hydroxyalkyl alkyl cellulose is mixed with a hydroxyalkyl cellulosic .

In the cellulose ether additive used in the mortar composition for cement mortar extrusion molding according to the present invention, the hydroxyalkylcellulose is mixed in an amount of 10 to 30% by weight based on the total weight of the additive.

Also, in the cellulose ether additive, the hydroxyalkyl alkyl cellulose preferably has an alkyl group degree of substitution (DS) of 0.20 to 2.0, a hydroxyalkyl group degree of substitution (MS) of 0.04 to 1.0, and the hydroxyalkyl cellulose is a hydroxyalkyl group It is preferable that the degree of substitution (MS) is 1 to 5

The mortar composition for cement mortar extrusion molding comprising a cellulose ether additive containing hydroxyalkyl cellulose in the hydroxyalkyl alkyl cellulose according to this embodiment may be mixed with a mortar composition for cement mortar extrusion molding containing a dry mix composed of cement, silica sand, fine aggregate, polypropylene fiber and other additives Raw materials are used, and water is included in the outer rim.

The composition ratio of each of the constituents constituting the mortar composition for cement mortar extrusion molding is preferably 40 to 60% by weight of cement, 20 to 40% by weight of silica sand, 5 to 15% by weight of fine aggregate, 0.1 to 3% by weight of polypropylene fiber, And 0.1 to 10% by weight of other additives, wherein the content of the cellulose ether additive in which the hydroxyalkyl alkyl cellulose is mixed with hydroxyalkyl cellulose is in the range of 0.1 to 5% by weight, the water is added in an amount of 10 to 40% And is included in the outer limits within the range of negative.

In this case, when the cellulose ether additive is used in an amount of less than 0.1% by weight, water retention and lubricity may be lacking, which may cause cracks in the pressed product, and when used in an amount exceeding 5% by weight, Which is undesirable.

As the cement, hydraulic cements such as Portland cement, fly ash cement and aluminum containing cement may be used, and color cement or the like may be used. If necessary, it may be used in combination with semi-gypsum, slaked lime, calcium carbonate, dolomite plaster, and / or clay

The fine particulate aggregate refers to an aggregate having a size of 100 mesh or less, and may be, for example, a quartz sand.

The polypropylene fibers may be fibers having a length of 10 to 30 mm and a diameter of 1 to 10 mm, but are not limited thereto.

In addition to the above, other additives may be used as needed within the range commonly used in this field. Specifically, wollastonite, fiber materials, antifoaming agents and the like may be used.

The mortar for cement-based extrusion molding of the above composition has a degree of methyl group substitution and another hydroxyethyl group substitution degree range with respect to the cellulose ether selected from hydroxypropylmethyl cellulose or hydroxyethyl methyl cellulose having a degree of substitution of hydroxypropyl or hydroxyethyl group The gelation of the cellulose ether in the extruded mortar exposed to the high temperature for a long time is prevented and the water retention property is increased so as to improve the water retention of the cellulose ether. It is possible to provide an extrusion molded panel excellent in forming and lubricating properties.

The mortar composition for cement mortar extrusion molding according to another embodiment of the present invention comprises the steps of: weighing cement, silica sand, cellulose pulp, polypropylene fiber, and cellulose ether additive in desired amounts; Dry mixing the cement, silica sand, fine aggregate, polypropylene fiber, and cellulose ether additive; Wet mixing the water into the dry mixed mixture; And introducing the mixture into the extruder after completion of the wet mixing.

In the dry mixing step, cement, silica sand, cellulose-based pulp, polypropylene fiber and cellulose ether additive are mixed and mixed without adding water. In the wet mixing step, water (compounding water) do.

Hereinafter, the present invention will be described in more detail based on the following examples, but the present invention is not limited by the following examples.

Examples 1 to 6

Cellulose ether additive manufacturing

Cellulose ether additives 1, 2 and 3 were prepared by mixing 10% by weight, 20% by weight and 30% by weight of hydroxyethyl cellulose with 90% by weight, 80% by weight and 70% by weight of hydroxypropyl methylcellulose, respectively, Cellulose ether additives 4, 5 and 6 were prepared by mixing 10% by weight, 20% by weight and 30% by weight of hydroxyethyl cellulose with 90% by weight, 80% by weight and 70% by weight of ethyl methyl cellulose.

Mortar production for cement extrusion molding

Cement, silica sand, fine aggregate, polypropylene fiber, and the cellulose ether additives 1 to 6 prepared above were prepared in the amounts shown in Table 1 below, mixed in a dry manner for uniform dispersion between these raw materials, Water was added and wet mixed to prepare mortar for cement-based extrusion molding. The water used in Table 1 was applied as an external mortar at the total weight (%).

Comparative Examples 1 to 2

Except that hydroxypropylmethylcellulose or hydroxyethylmethylcellulose was used alone without mixing hydroxyethylcellulose in the same manner as in Examples 1 to 6 above to prepare mortar for cement-based extrusion molding .

weight% Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 cement 52 52 52 52 52 52 50 50 Silica sand 32 32 32 32 32 32 32 32 No. 8 10 10 10 10 10 10 10 10 Wollastonite 5 5 5 5 5 5 5 5 Polypropylene fiber 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 HPMC - - - - - - 0.7 - HEMC - - - - - - - 0.7 CE Additive 1 0.7 - - - - - - - CE Additive 2 - 0.7 - - - - - - CE Additive 3 - - 0.7 - - - - - CE Additive 4 - - - 0.7 - - - - CE Additive 5 - - - - 0.7 - - - CE Additive 6 - - - - - 0.7 - - total 100 100 100 100 100 100 100 100 water 27
Outside 27
Outside 27
Outside 27
Outside 27
Outside 27
Outside 27
Outside 27
Outside

HPMC: hydroxypropylmethylcellulose (DS: 1.4 and MS: 0.2)

HEMC: hydroxyethyl methylcellulose (DS: 1.5 and MS: 0.3)

HEC: hydroxyethylcellulose (MS: 2.5)

Cement: 1 species Usually Portland cement (Dongyang cement)

Silica sand: S-SIL 15 (SA Pure SILICA)

8 Company: Sand 8 Company (Kyungin Material)

Wollastonite: Wollastonite (HB-325M)

Polypropylene Fiber: Industrial Polypropylene Chemical Fiber

Evaluation example 1

The mortar composition of Examples 1 to 6 and Comparative Examples 1 and 2 was mixed with a cement, a silica sand, a No. 8 quartz, a wollastonite, a polypropylene fiber and a cellulose ether additive, and then water was added thereto. After mixing, the mixture was placed in an extruder connected to a cold / hot circulation apparatus and allowed to stand for 0, 20, 40, and 60 minutes. Then, retentivity, extrusion resistance and cracking were evaluated. Respectively.

Retentivity : The mortar was put into the extruder and allowed to stand for 0, 20, 40, and 60 minutes. The smoothness of the surface of the extruded mortar was measured and converted into a score based on the score of 5.

Extrusion Resistance : The mortar was put into the extruder and left for 0, 20, 40, and 60 minutes, and the resistance (MPa) at the time of extrusion was measured.

Crack occurrence : The occurrence of cracks in release of mortar soil was confirmed and observed.

Residence property Extrusion resistance (MPa) Cracking 0 minutes 20 minutes 40 minutes 60 minutes 0 minutes 20 minutes 40 minutes 60 minutes 0 minutes 60 minutes Example 1 4.5 4.3 4.1 4.0 3.22 3.36 3.51 3.78 none none Example 2 4.5 4.3 4.0 3.8 3.22 3.38 3.55 3.78 none none Example 3 4.5 4.3 4.0 3.8 3.22 3.40 3.57 3.80 none none Example 4 4.5 4.3 4.0 3.8 3.22 3.38 3.64 3.92 none none Example 5 4.5 4.3 3.9 3.7 3.22 3.40 3.65 3.92 none none Example 6 4.5 4.3 3.8 3.7 3.22 3.41 3.65 3.92 none none Comparative Example 1 4.5 3.8 3.8 3.3 3.22 3.75 3.92 4.23 none Occur Comparative Example 2 4.5 3.8 3.6 3.0 3.22 3.53 3.83 4.03 none Occur

As can be seen from the above Table 2, Comparative Examples 1 and 2 are mortar using a cellulose ether additive in which hydroxyethyl cellulose is not incorporated, so that the surface state can not be formed smoothly, Respectively. Also, cracking occurred after standing for 60 minutes, resulting in poor extrusion. On the other hand, in Examples 1 to 6 in which additives such as hydroxypropylmethylcellulose or hydroxyethylmethylcellulose containing 10% by weight, 20% by weight and 30% by weight of hydroxyethylcellulose were applied, the retention was relatively improved, Resistance was relatively low during extrusion, and cracking did not occur after residence for 60 minutes.

Therefore, when a certain amount of hydroxyethylcellulose was mixed with hydroxypropylmethylcellulose or hydroxyethylmethylcellulose alone, it was found that satisfactory retention and extrusion resistance affecting moldability were obtained, and material separation and cracking did not occur And excellent surface state was observed, so that the extrusion moldability was improved.

Evaluation example 2

The degree of retardation with respect to the setting time for the extruded mortar prepared in Examples 1 and 4 and Comparative Examples 1 and 2 was measured with an Ultrasonic Multiplex Tester (IP-8) ultrasonic tester, and the results are shown in FIG. In FIG. 1, the velocity (m / s) represents the cementation rate (the rate at which the cement is condensed with time) and the time (min) represents the cementation time.

As can be seen from FIG. 1, in Examples 1 and 4 in which an additive containing 10% by weight of hydroxyethylcellulose was added to hydroxypropylmethylcellulose or hydroxyethylmethylcellulose, the setting time was further delayed Could know.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims

Cellulose ether additive for mortar for extrusion molding of cement based on hydroxyalkyl alkylcellulose mixed with hydroxyalkylcellulose.

The method according to claim 1,
Wherein the hydroxyalkylcellulose is mixed in an amount of 10 to 30% by weight based on the total weight of the cellulosic ether additive.

The method according to claim 1,
Wherein the hydroxyalkyl alkyl cellulose has an alkyl group degree of substitution (DS) of 0.20 to 2.0, a hydroxyalkyl group degree of substitution (MS) of 0.04 to 1.0, and the hydroxyalkyl cellulose has a hydroxyalkyl group degree of substitution (MS) 5 Cementitious extruded cellulose ether additive for mortar.

The method according to claim 1,
Wherein the hydroxyalkylalkylcellulose is hydroxypropylmethylcellulose or hydroxyethylmethylcellulose, and the hydroxyalkylcellulose is hydroxyethylcellulose; and the cellulose ether additive for cement mortar.

In a mortar composition for cement mortar extrusion molding,
A mortar composition for cement mortar extrusion molding comprising a cellulose ether additive for mortar according to any one of claims 1 to 4.

6. The method of claim 5,
Wherein the cellulose ether additive is contained in an amount of 0.1 to 5% by weight based on the total weight of the mortar composition.

6. The method of claim 5,
From 20 to 40% by weight of a cement, 20 to 40% by weight of a silica sand, 5 to 15% by weight of a fine aggregate, 0.1 to 3% by weight of a polypropylene fiber, 0.1 to 5% by weight of a cellulose ether additive and 0.1 to 10% And 10 to 40 parts by weight of water is added to the mortar composition for cement mortar extrusion molding.