BR102015024934A2 - handle retardant additive formulation - Google Patents

Abstract

handle retardant additive formulation. The present invention relates to a handle retardant additive formulation comprising organic amines, for example monoethanolamine and diethanolamine, preferably triethanolamine; an alcohol, preferably being the c3 chain compound glycerin which may be distilled or derived from biodiesel and a glycol, a glycol such as monoethylene glycol, diethylene glycol or triethylene glycol may be added to the formulation. Such a formulation, when applied to the cement paste, will provide a concrete with improved grip retention characteristics and mechanical strength.

Description

HANDLING DELAY ADDITIVE FORMULATION

FIELD OF INVENTION

[001] The present invention is in the field of Industrial Chemistry, more specifically in the field of specialized chemicals, and describes a concrete applied retardant additive formulation comprising the mixture of triethanolamine, glycerin and glycol.

BACKGROUND OF THE INVENTION

[002] Concrete additive technology in the construction market has advanced significantly in this century, always envisaging operational excellence in order to obtain the best material for a given application at the lowest possible cost.

[003] In Brazil the main additives used are: retarders, air incorporators, plasticizers, superplasticizers and accelerators.

[004] One of the main characteristics sought in the additive would be workability, increased final strength in order to obtain the material with greater durability, as mentioned in ISAIA, G. C. (ed.). Concrete: teaching, research and achievements. São Paulo: Ibracon, 2005 and MENDES NETO, F. Advanced Structural Concrete: analysis of cross sections under normal composite flexion. Sao Paulo: Pini, 2009.

[005] The classification of additives is standardized like ABNT-NBR-11768: 2011, where upon application results the additive may fall into some classes as accelerator or retarder and so on.

[006] Additives, handle retardants as the name implies, are generally intended to delay the onset of the concrete handle, ie to delay the hardening process of the concrete.

[007] In the class of handle accelerators commonly used are alkaline and alkaline earth element salts and organic compounds with organic amines as reference in the book MARTIN, J. F. M. Concrete additives: concrete, teaching, research and achievements. In: IBRACON. Additives for concrete. Vol.1, chap.13. Sao Paulo: IBRACON, 2005, p.381-406. Accelerators generally increase initial resistance by reducing exudation and segregation.

Some additives classified as accelerators upon dosing in concrete may have the reverse effect demonstrating characteristic of retarding additives.

[009] The prefabricated industry in Brazil which is responsible for manufacturing industrially produced or molded elements with standardized dimensions such as: stairs, foundations, galleries, panels, walkways, pillars, bridges and viaducts, beams, among others, It uses handle retardant additives extensively in order to get longer time to work with the material.

[010] The characteristic of delaying the handling of the concrete constituent cement is important for the industry as it allows to maintain the concrete workability for a certain time, delaying the increase of the cement hydration heat, thus increasing the material application time. . Many formulations contribute to the increased strength of concrete as this class of additives may also favor the heat of cement hydration.

[011] Commonly applied as handle retardant additives are carbohydrates (sugars), hydroxy carboxylic and dicarboxylic acids, phosphates and lead and zinc salts.

For handle reducing formulations many formulations may be employed, for example: [013] The product described in JP-A-1-172250 mentions the application of the following products as cement retardants: inorganic compounds such as zinc oxide , borax and organic compounds as polyhydroxylated compounds (alcohols, methylcellulose, ethylcellulose, dextrin).

The retardant used in the mortar composition described in US7740701B2 comprises a C4 A chain polyhydroxylated compound C12 · [015] The retardant additive described in EP2726435A1 comprises reaction product of a polyhydroxylated compound and borax applied in cementation. of drilling fluids. In such a formulation, for example, said polyhydroxylated compound may be a sugar, such as a gluconic acid, gluconate or glucoheptonate or a salt thereof.

WO2014139857A1 describes the use of an aqueous composition containing at least one polycarboxylate ether as a cement grinding additive. The aqueous composition contains one or more additives or is used in combination with one or more additives, and the additives are selected from 1,3-propanediol, a carboxylic acid, an amino sulfonated alcohol, boric acid, a boric acid salt. , a phosphoric acid salt, sorbitol, a saccharide, a gluconate, iron sulfate, tin sulfate, antimony salt, an alkaline salt thereof, an alkaline earth metal salt, lignosulfonate, glycerin, melamine, melamine sulfonate, and their mixtures.

Thus, the prior art documents deal with handle reducing formulations which have various products in their composition, however none of these specifies the combined use of the polyhydroxylated compound belonging to the C3 chain alcohol glycerine family. together with an organic amine and glycol, envisioning an ideal formulation for reducing cement / concrete grip, let alone the ranges of this combination in which glycol can be added.

[018] As can be seen, the use of organic amines in handle retardant additive formulations is already well known. Thus, the present invention arises with the proposal of an alternative formulation the use of only organic amines for the handle retention function also envisaging improvements in the strength of the final concrete.

BRIEF DESCRIPTION OF THE INVENTION

[019] The present invention aims to obtain a formulation in which it provides a concrete with improved grip retention characteristics and mechanical strength and thus proposes a concrete retardant handle additive formulation comprising the mixture of triethanolamine, glycerin and glycol.

DETAILED DESCRIPTION OF THE INVENTION

[020] Δ The present invention relates to an alternative formulation for a handle retardant consisting essentially of organic amines, preferably ethanolamines, which provide better properties for the handle retention function and also lead to improvements in the strength of the final concrete. .

In order to obtain the formulation of the present invention an organic amine was used, such as monoethanolamine and diethanolamine, preferably triethanolamine; and polyhydroxylated compounds, preferably being the C3 chain compound, glycerin, which may be distilled or derived from biodiesel and a glycol, which may be a monoethylene glycol, diethylene glycol or triethylene glycol.

Considering their ratio, the preferred dosage ranges are: 30% to 90% triethanolamine, 10% to 70% glycerine and 10% to 70% glycol.

[023] Table 1 below presents the application-tested formulations that gave the best results by obtaining good handle retention as well as elevations in the strength of the final concrete.

Table 1: Tested Formulations Raw Material _______________________1______2______3______4_____5 Triethanolamine 90 30 80 90 30 Glycerin 10 70 10 Glycol 10 10 70 [024] Such a formulation may be substituted for ethanolamine in the formulation of handle retardant additives or may be applied directly to concrete in the dosage of 0.2% to 5.0% on the mass of constituent cement in concrete. Increasing the concentration of the additive increases the delay property of the start of the handle.

In view of the results obtained, glycols can also be used in this formulation, due to synergism of the molecule in the application, which can be dosed in the proportion of 10% to 70%.

[026] Due to the synergistic interaction of the formulation constituents, the application tests show a slight increase in the mechanical strength of the concrete, a feature that is very much desired by industry.

[027] Although the invention has been widely described, it is obvious to those skilled in the art that various changes and modifications may be made to improve the design without such changes being covered by the scope of the invention.

Claims (7)

1. A handle retardant additive formulation comprising: - 30 to 90% amine; - from 10 to 70% of an alcohol; and - from 10 to 70% of a glycol. Formulation according to Claim 1, characterized in that the amine is based on ethanolamine, such as monoethanolamine or diethanolamine, preferably triethanolamine. Formulation according to Claim 1, characterized in that the alcohol is preferably a C3 chain compound. Formulation according to Claim 3, characterized in that the C3 chain compound is glycerin, which may be distilled or derived from biodiesel. Formulation according to Claim 1, characterized in that the glycol is monoethylene glycol, diethylene glycol or triethylene glycol. Formulation according to any one of claims 1 to 5, characterized in that it is applied directly in the dosage 0.2% to 5.0% on the constituent cement mass in the concrete. Formulation according to any one of claims 1 to 6, characterized in that the synergistic interaction of the constituents generates a slight mechanical strength of the concrete.