Description:TECHNICAL FIELD
[0001] The present disclosure pertains to the field of construction materials and, more specifically, to a method for preparing a mortar composition suitable for self-curing plaster applications. The disclosure particularly relates to the incorporation of Polyethylene Glycol (PEG) as an internal curing agent to minimize moisture evaporation, enhance cement hydration, and reduce or eliminate the need for external curing in high-strength mortar and plaster systems.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present disclosure. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed disclosure, nor that any publication specifically or implicitly referenced is prior art.
[0003] Concrete and mortar are fundamental materials in construction, valued for their strength and adaptability. However, traditional cementitious materials face inherent challenges, such as autogenous shrinkage during hydration, which can lead to early-age cracking, compromising mechanical properties and durability. Conventional water curing methods, while effective to some extent, are labor-intensive, resource-demanding, and often impractical in tall structures or arid regions. Internal curing has emerged as a promising solution to address these challenges. The internal curing techniques involve embedding water reservoirs within the cementitious matrix to provide sustained moisture during hydration, thereby reducing shrinkage and improving mechanical strength and durability.
[0004] Various internal curing strategies have been explored in the past, including the use of lightweight aggregates, superabsorbent polymers (SAPs), and porous materials. Although these methods are effective in specific applications, they often introduce practical limitations related to mix design complexity, material availability, cost, and compatibility with conventional plastering practices. Additionally, some internal curing agents may adversely affect the workability, strength, or setting characteristics of the mortar, limiting their widespread adoption in plastering applications.
Therefore, there exists a need for a simplified, sustainable, and efficient method for preparing a self-curing mortar composition, particularly suitable for plaster applications.

OBJECTS OF THE INVENTION
[0005] Some of the objects of the present disclosure, which at least one embodiment seeks to fulfill, are set forth below. These objects are intended to illustrate the scope and utility of the invention, without limiting the claims.
[0006] A primary object of the present disclosure is to provide an effective method for preparing a mortar composition suitable for self-curing plaster by incorporating Polyethylene Glycol (PEG) as an internal curing agent, thereby effectively mitigating evaporation and promoting sustained cement hydration in high-performance mortar applications.
[0007] Another object of the present disclosure is to develop a self-curing mortar mix that significantly reduces or eliminates the need for external water curing, thereby making it suitable for use in environments with limited water availability or where access to cured surfaces is restricted, such as in tall buildings or remote construction sites.
[0008] Another object of the present disclosure is to enhance the performance of plastered surfaces by improving the microstructural integrity, reducing shrinkage-induced cracking, and increasing mechanical strength and long-term durability, which collectively contribute to minimizing repair frequency and lifecycle costs. Yet another object of the present disclosure is to provide a cost-effective and user-friendly solution that is compatible with standard mortar mixing practices and does not require significant changes to existing tools, equipment, or labor skills, thereby enabling seamless integration into current construction workflows.

SUMMARY
[0009] Aspects of the present disclosure relates to the field of construction materials. In particular, it relates to a method for preparing a mortar composition for self-curing plaster using Polyethylene Glycol (PEG) as an internal curing agent, to effectively reduce moisture evaporation and enhance cement hydration, thereby improving the performance of high-strength mortar compositions.
[0010] An aspect of the present disclosure relate to a method for preparing a mortar composition including the steps of preparing a binding paste, mixing a predefined amount of one or more admixtures into the binding paste to form a blended mixture; and subsequently mixing a predetermined dosage of an internal curing agent into the blended mixture to obtain the final mortar composition.
[0011] In an embodiment, the step of preparing the binding paste may include mixing a predefined amount of one or more binders with a predefined ratio of one or more raw materials.
[0012] In an embodiment, the one or more binders may be selected from any one or a combination of: cement, silica fume and Ground Granulated Blast furnace Slag (GGBS).
[0013] In an embodiment, the method may include mixing a predetermined amount of water with the one or more binders and the one or more raw materials to form the homogeneous binding paste.
[0014] In an embodiment, the curing agent may be at least a Polyethylene Glycol (PEG), which facilitates self-curing by retaining moisture within the matrix during the hydration process.
[0015] In an embodiment, the curing agent may be added in a predetermined dosage range of about 0.5% to 2% by weight of the total cementitious content.
[0016] In an embodiment, the one or more admixtures may include at least a superplasticizer to enhance the workability and dispersion of particles in the mortar mix.
[0017] Another embodiment of the present disclosure pertains to a mortar composition. The mortar composition may include a predetermined dosage range of curing agent, a predefined amount of one or more admixtures, a predefined amount of one or more binders, a predefined ratio of one or more raw materials and a predetermined ratio of water. The curing agent and the one or more admixtures may be mixed with a mix of the one or more binders, the one or more raw materials, and the water to prepare the mortar composition.
[0018] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying figures in which like numerals represent like components.

BRIEF DESCRIPTION OF DRAWINGS
[0019] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0020] FIG. 1 illustrates an exemplary flow diagram representing a method for preparing a mortar composition, in accordance with an embodiment of the present disclosure.
[0021] FIG. 2A illustrates a graphical representation of compressive strength of various mixes, in accordance with an embodiment of the present disclosure.
[0022] FIG. 2B illustrates a graphical representation of impact resistance of mortar samples, in accordance with an embodiment of the present disclosure.
[0023] FIG. 2C illustrates a graphical representation of mass and strength losses due to abrasion in mortar samples, in accordance with an embodiment of the present disclosure.
[0024] FIG. 2D illustrates a graphical representation of compressive strength variation after each wet-dry test cycle, in accordance with an embodiment of the present disclosure.
[0025] FIG. 2E illustrates a graphical representation of shrinkage strain of mortar mixes, in accordance with an embodiment of the present disclosure.
[0026] FIG. 2F illustrates a graphical representation of fire resistance of mortar mixes, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0027] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0028] Embodiments of the present disclosure relates to the field of construction materials. In particular, it relates to a method for preparing a mortar composition for self-curing plaster using Polyethylene Glycol (PEG), thereby effectively mitigating evaporation and promoting enhanced cement hydration in the high-performance mortar.
[0029] An embodiment of the present disclosure relate to a method for preparing a mortar composition. The method may include preparing a binding paste, mixing a predefined amount of one or more admixtures in the prepared binding paste to form a blended mixture and mixing a predetermined dosage range of curing agent in the blended mixture to prepare the mortar composition.
[0030] FIG. 1 illustrates an exemplary flow diagram representing a method (100) for preparing a mortar composition in accordance with an embodiment of the present disclosure.
[0031] Referring to FIG. 1, at block (102), the method (100) may include preparing a binding paste. The binding paste may be prepared by mixing a predefined amount of binders with a predefined ratio of raw materials to prepare the binding paste. The binders may be selected from any one or a combination of cement, silica fume and Ground Granulated Blast furnace Slag (GGBS). The cement used can be for instance, Ordinary Portland Cement (OPC) having 53 grade. In an example embodiment, the materials may be, for instance, fine aggregates such as manufactured sand, crushed stone or the like. The fine aggregates may have a significant impact on the strength of the mortar and the quality of fine aggregates may greatly affect the quality of mortar.
[0032] Further, the method (100) may include mixing a predetermined ratio of water with the binders and the raw materials to prepare the binding paste. The predetermined water ratio may be calculated to ensure that the mortar composition has the desired consistency and workability for application. More water may weaken the mortar by creating excessive voids, while less water may make the mixture too stiff, reducing the workability of the mortar composition and potentially leading to incomplete hydration of the cement. The water-binder ratio may ensure optimal balance between workability and strength in the mortar composition.
[0033] At block (104), the method (100) may include mixing a predefined amount of admixtures in the prepared binding paste to form a blended mixture. The admixtures may be chemical admixtures, preferably superplasticizers such as Polycarboxylate Ether (PCE) or Sulphonated Naphthalene Formaldehyde (SNF) that may be mixed into the binding paste to improve flowability and dispersion.
[0034] In an example embodiment, the properties of the superplasticizers may be as shown in Table 1.
Table 1 – Properties of Superplasticizers

[0035] At block (106), a predetermined dosage of internal curing agent such as Polyethylene Glycol (PEG), typically in the range of 0.5% to 2.0% by weight of the cementitious content, may be incorporated. PEG (e.g., PEG 4000 or PEG 6000), owing to its hygroscopic and film-forming characteristics, creates a thin surface layer over the cement particles and within the pore structure. The thin surface layer may act as a barrier that slows down the evaporation of moisture from the mix, thereby retaining water within the matrix for an extended period. As a result, the mortar may undergo more uniform and sustained hydration, leading to improved microstructural density, reduced autogenous shrinkage, and enhanced mechanical performance, which is especially advantageous in plastering applications where external curing is difficult or impractical.
[0036] In an example embodiment, the properties of the curing agent may be as shown in Table 2.
Table 2 - Properties of Curing Agent

[0037] In an example embodiment, for experimentation, physical, mechanical, and durability characteristics of various mixes were analyzed. The various mixes may be divided into 4 categories viz., (1) mix with superplasticizer and curing agent, (2) mix with only curing agent, (3) mix with superplasticizer cured conventionally, and (4) mix with superplasticizer cured at room temperature. The various mixes is as shown Table 3.
Table 3 – Mixes for Mortar Composition

[0038] FIGs. 2A to 2F illustrate graphical representations of mechanical and durability properties (200A to 200F) of various mixes, in accordance with an embodiment of the present disclosure.
[0039] Referring to FIGs. 2A to 2F, based on the experimentation, the flow studies on internally cured cement paste revealed that both PEG 4000 and PEG 6000 have shown better flow characteristics when mixed with PCE based superplasticizer, providing additional lubrication and reduced water evaporation, maintaining a workable consistency for a longer period. The retained water may also plasticize the cement paste, further enhancing flow. Additionally, PEGs may have a low coefficient of friction, acting as lubricants within the cement paste. Further, the results demonstrate that PEG 4000 and PEG 6000 may be used in internal curing applications when combined with PCE-based superplasticizers, improving the mechanical properties and durability of mortar mixes. The mixes consisting of PCE based superplasticizer in combination with curing agents (PP6&PP4) had about 14% higher strength than the mixes with SNF based superplasticizer in combination with curing agents (SP6&SP4) (as shown in FIG. 2A).
[0040] The impact studies yielded results consistent with those obtained from the compressive strength tests. As compared to the mortar mixes without PEG 6000, the mortar mixes in which PEG 6000 was incorporated displayed a higher number of blows (thereby increasing impact resistance), averaging 19 blows for the appearance of initial and final cracks (as shown in FIG. 2B). Comparatively, PEG 4000 mixes required approximately 16 blows (indicating lower impact resistance), indicating that PEG 6000 is more effective in facilitating internal moisture release compared to PEG 4000.
[0041] The mixes incorporating PCE based superplasticizers in conjunction with PEG 4000 and PEG 6000 exhibited the most favorable outcome, characterized by the lowest mass loss and concurrently higher strength when compared to all other internally cured mixes incorporating superplasticizers (as shown in FIG. 2C). In contrast, the mixes containing solely PEG 6000 and PEG 4000 demonstrated comparable levels of mass loss and strength reduction, suggesting the efficacy of the curing agents, specifically PEG 4000 and PEG 6000, in facilitating adequate internal moisture for enhanced performance under abrasive conditions.
[0042] Further, a uniform reduction of approximately 25% in compressive strength was observed across all mix types upon the completion of 15 cycles (as shown in FIG. 2D). The PP6 and PP4 mixes had the least loss in compressive strengths while the highest strength loss was observed for room cured mixes (PSP-RC, SSP-RC), indicating that PEG 6000 and PEG 4000 may have a better compatibility with PCE based superplasticizers in retaining the strength property. The PP6 and PP4 mixes had the least loss in compressive strengths while the highest strength loss was observed for room cured mixes (PSP-RC, SSP-RC). This indicates that PEG 6000 and PEG 4000 has a better compatibility with PCE based superplasticizers in retaining the strength property (as shown in FIG. 2E). Further, room-cured mixes exhibited the highest degree of strength loss when subjected to temperature in the range of from 200°C to 600°C, whereas PP6 and PP4 formulations demonstrated the lowest strength loss (as shown in FIG. 2F), indicating that proper curing procedures significantly enhance the fire resistance.
[0043] Further, the results may indicate that by optimizing the dosage range and type of PEG, the effectiveness of internal curing may be enhanced and strength loss under wet-dry cycling may be minimized. The use of PEG may also slower drying process, because of the internal curing produced by PEGs and improved workability produced by PCEs. The chemistry of superplasticizers with PEGs may have played a crucial role in determining the fresh and hardened properties of mortar. The structure (long, comb-like molecular structure) may allow PCEs to adsorb onto the surface of cement particles, imparting a steric hindrance effect that prevents particle agglomeration. As a result, PCEs enhance the flowability and workability of the mortar without requiring additional water.
[0044] Thus, the present disclosure introduces a method for preparing a mortar composition suitable for self-curing plastering applications. By incorporating Polyethylene Glycol (PEG) into the cement mortar in controlled dosages ranging from 0.5% to 2.0% by weight of the cementitious material, the composition is endowed with internal curing capability. The PEG may allow the mortar to retain and gradually release water during the hydration process, thereby enhancing cement hydration, reducing autogenous and drying shrinkage, and improving the overall mechanical properties and durability of the plastered surfaces.
[0045] While the foregoing describes various embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The scope of the disclosure is determined by the claims that follow. The disclosure is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the disclosure when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION
[0046] The present disclosure provides a self-curing mortar composition that eliminates a need for external water curing, making it highly suitable for use in water-scarce regions and inaccessible construction sites.
[0047] The present disclosure provides an internally curing mechanism using Polyethylene Glycol (PEG), which ensures sustained hydration of cement particles and leads to enhanced microstructural development.
[0048] The present disclosure provides improved durability and mechanical strength of plastered surfaces by minimizing shrinkage-induced cracking and increasing cement hydration efficiency.
[0049] The present disclosure provides a cost-effective solution that reduces labor requirements and curing-related supervision on construction sites, thereby improving project efficiency and reducing operational costs.
[0050] The present disclosure provides compatibility with conventional mixing and application methods, allowing for easy integration into existing construction practices without the need for specialized equipment or additives.
, Claims:1. A method (100) of preparing a mortar composition, the method (100) comprising:
preparing (102) a binding paste;
mixing (104) a predefined amount of one or more admixtures in the prepared binding paste to form a blended mixture; and
mixing (106) a predetermined dosage range of curing agent in the blended mixture to prepare the mortar composition.

2. The method (100) as claimed in claim 1, comprising mixing a predefined amount of one or more binders with a predefined ratio of one or more raw materials to prepare the binding paste.

3. The method (100) as claimed in claim 2, wherein the one or more binders are selected from any one or a combination of: cement, silica fume and Ground Granulated Blast furnace Slag (GGBS).

4. The method (100) as claimed in claim 2, comprising mixing a predetermined ratio of water with the one or more binders and the one or more raw materials to prepare the binding paste.

5. The method (100) as claimed in claim 1, wherein the curing agent is at least a Polyethylene Glycol (PEG).

6. The method (100) as claimed in claim 1, wherein the curing agent is in a predetermined dosage range of about 0.5% to 2%.

7. The method (100) as claimed in claim 1, wherein the one or more admixtures comprises at least a superplasticizer.

8. A mortar composition, comprising:
a predetermined dosage range of curing agent;
a predefined amount of one or more admixtures;
a predefined amount of one or more binders;
a predefined ratio of one or more raw materials; and
a predetermined ratio of water,
wherein the curing agent and the one or more admixtures are mixed with a mix of the one or more binders, the one or more raw materials, and the water to prepare the mortar composition.