Polymer based compositions for 3D printing

Abstract

The invention relates to compositions and use thereof in 3D printing. Specifically, the present invention relates to a composition comprising at least two polymers and a compatibilizer wherein the at least two polymers comprises of polymer 1 and polymer 2, the polymer 1 is a polyolefin selected from polypropylene (PP), polyethylene (PE) or combination thereof, the polymer 2 is a flexible polymer selected from poly(butylene adipate-co- terephthalate) (PBAT), polybutylene succinate, lactic acid-polyethylene glycol-lactic acid block co-polymer, thermoplastic polyurethane, polycaprolactone, polyethylene glycol or combination thereof, and wherein the compatibilizer is selected from maleic anhydride, maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene, grafted ethylene- propylene-diene monomer, thermoplastic elastomer, ethylene-methyl acrylate or combination thereof. The present invention also discloses a process of preparation of the composition. The invention further discloses a process for preparation of an article by 3D printing using the composition of the present invention.

Description

[0001] PT / 2025 / 14947

[0002] POLYMER BASED COMPOSITIONS FOR 3D PRINTING

[0003] FIELD OF THE INVENTION

[0004] The invention relates to compositions and its process for preparation. The invention also relates to a process for 3D printing by using the composition of the present invention. Specifically, the present invention relates to a composition comprising at least two polymers and a compatibilizer and a process of preparation thereof. The invention also relates to a production of 3D printed articles using said composition.

[0005] BACKGROUND OF INVENTION

[0006] Since its introduction during the 1980s, additive manufacturing, also known as 3D printing, has evolved into a versatile technology platform. Different 3D printing techniques facilitate the production of customized parts made of metals, ceramics, and polymers. These advanced digital manufacturing technologies for polymers have created new opportunities for sustainable lightweight construction, optimized process and component design, as well as the production of customized multi-functional, multi-material systems.

[0007] Among additive manufacturing techniques, material extrusion 3D printing, named fused filament fabrication (FFF), represents the most popular and widely used process in both industry and the private sector. The robust and cost-effective design of FFF and the production of finished components that do not necessarily require post-processing are the key factors in this technique. Good adhesion of the printed objects on the build plate without impairing their facile detachment; efficient, strong fusion of the deposited polymer strands; and, most importantly, a low tendency to warp due to volume shrinkage of the polymer during solidification are the most critical material requirements in material extrusion 3D printing specifically in FFF.

[0008] Despite a greater than 50% share of the global plastics market, polyethylene (PE) and polypropylene (PP) are still rarely used in 3D printing. The semi-crystalline nature of PE and PP causes massive volume shrinkage and drastic warpage by polymer crystallization in FFF. However, PP exhibits an exceptionally balanced property range of mechanics, low density, processability, and chemical resistance to common polar solvents, and many acids and bases. Moreover, its high cost-, resource-, and energy-efficiency, solvent-free catalytic PT / 2025 / 14947 polymerization as well as its easy recyclability as materials and as a source of both chemical feedstocks and energy, make PP one of the leading polymers in life cycle assessments, far ahead of biopolymers.

[0009] Various approaches have been pursued to overcome the warpage problem of semi-crystalline polyolefins. Carneiro et al. Mater. Des. 2015, 83, 768- 776 (DOI:

[0010] 10.1016 / j.matdes.2015.06.053), established the fundamental basis for minimizing thermal distortion of neat PP through FFF process control using optimized printing parameters and printing pathways, as well as improved build plate adhesion. However, the printed specimens exhibited up to a 30% loss of mechanical performance compared with compression-molded specimens made of the same material.

[0011] The addition of fillers to optimize the printability and build precision of PP in FFF is another versatile approach. A variety of organic and inorganic fillers have been investigated as PP compounds for use in extrusion-based 3D printing. Both fillers with low aspect ratios, such as talc, glass beads, pearlite, or gypsum, and fillers with high aspect ratios, including glass, carbon, and various natural fibers, have resulted in lower warpage. In all such cases, uniform dispersion of the filler in the PP matrix has been crucial for reducing thermal shrinkage (refer, Spoerk, M. et al., Composites, Part A, 2018, 113, 95-104). The reduction of the crystallinity on the molecular level and the associated lower thermal shrinkage represent another common approach to minimizing PP warpage. However, this and other known approaches to improve the build precision of PP in FFF are associated with manifold drawbacks such it bears the risk of generating stress caused by thermal shrinkage that are only temporarily frozen and may cause subsequent deformation and warpage at elevated temperatures. Further, random copolymers exhibit lower heat distortion temperatures owing to their reduced crystallinity and thus, fail to be competitive with PP homopolymers in typical commercial PP applications. Furthermore, such approaches may suffer from lesser elongation point for break, and do not achieve optimum toughness and brittleness.

[0012] Therefore, there is a need to develop a composition which will be easy to use for 3D printing with lesser, minimal or without warpage and balanced / desired mechanical properties such as optimum roughness, lesser brittleness and improved elongation point for break. Thus, the inventors of the present invention have successfully addressed the drawbacks of the available literature in order to effectively obtain 3D printed products via FFF technique by employing the composition of the present invention. PT / 2025 / 14947

[0013] OBJECTIVES OF THE INVENTION

[0014] An objective of the present invention is to provide a composition for 3D printing comprising at least two polymers and a compatibilizer.

[0015] Another objective of the invention is to provide a process for preparation of said composition comprising at least two polymers and a compatibilizer.

[0016] Yet another objective of the invention is to provide a 3D printed article using said composition.

[0017] SUMMARY OF THE INVENTION

[0018] In an aspect, the present invention relates to a composition comprising: i. at least two polymers; and ii. a compatibilizer; wherein the at least two polymers comprises of polymer 1 and polymer 2; the polymer 1 is a polyolefin selected from polypropylene, polyethylene or combination thereof; the polymer 2 is a flexible polymer selected from poly(butylene adipate-co-terephthalate) (PBAT), polybutylene succinate, lactic acid-polyethylene glycol-lactic acid block copolymer, thermoplastic polyurethane, polycaprolactone, polyethylene glycol or combination thereof; and wherein the compatibilizer is selected from maleic anhydride, maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene, grafted ethylene-propylene-diene monomer, thermoplastic elastomer, ethylene-methyl acrylate or combination thereof.

[0019] In another aspect, the present invention relates to a process for preparation of the composition as claimed in claim 1, by mixing at least two polymers with a compatibilizer to obtain a blend followed by melting the blend in a twin screw extruder at a temperature in a range from 200°C- 230 °C and at a speed in a range from 60 rpm (rotations per minute) to 120 rpm, for a time period in a range from 3 minutes to 7 minutes to obtain the composition. PT / 2025 / 14947

[0020] In another aspect, the present invention relates to a process for preparing an article by 3D printing, the process comprising: a) feeding the composition of the present invention into a nozzle of the 3D printer; b) heating a build plate at a temperature in a range of 80-110 °C and the nozzle of the 3D printer at a temperature in a range from 190-230°C; c) passing the composition through the heated nozzle; and d) extruding the heated composition from the nozzle with a printing speed in the range of 30 mm / sec to 70 mm / sec on the build plate to obtain the 3D printed article.

[0021] ABBREVIATIONS: rPP: Recycled polypropylene

[0022] PBAT: Poly(butylene adipate-co-terephthalate) rPP-1: Composition of the present invention containing specific weight ratio of rPP:PBAT (80:20) rPP-2: Composition of the present invention containing specific weight ratio of rPP:PBAT (70:30) rPP-3: Composition of the present invention containing specific weight ratio of rPP:PBAT (60:40) rPP-4: Composition of the present invention containing specific weight ratio of rPP:PBAT (70:30) rPP-5: Composition of the present invention containing specific weight ratio of rPP:PBAT (80:20)

[0023] The notations provided in figures are: A is for rPP product; B is for PBAT product, C is for rPP-1 composition of the present invention; D is for rPP-2 composition of the present invention; E is for rPP-3 composition of the present invention; and F is for rPP-4 composition of the present invention. Here, rPP-1 & rPP-5, and rPP-2 & r-PP-4 contain the same ratio of rPP and PBAT with different compatibilizer amount. PT / 2025 / 14947

[0024] BRIEF DESCRIPTION OF THE DRAWINGS:

[0025] Figure 1 shows schematic process steps covered in 3D printing of the compositions of the present invention. Here, numerals represents: 1 - Twin screw extruder; 2 - extruded filament spool; 3: Filament spool as a feed for 3D printer; 4 - Printing nozzle; 5 - Printed layer structure; 6 - Build plate; and 7 - Printed part for warpage quantification.

[0026] Figure 2 shows images of the 3D printed products based on individual rPP (Comparative Example A), and the composition rPP-5 of Example 1 of the present invention.

[0027] Figure 3 shows comparison graph of tensile stress vs elongation of 3D printed tensile bars of compositions (rPP- 1 to rPP-4) of the present invention over individual polymer rPP and PB AT.

[0028] Figure 4 shows comparison graph of toughness of 3D printed tensile bars of compositions (rPP-1 to rPP-4) of the present invention over individual polymer rPP and PBAT.

[0029] Figure 5 shows comparison graph of tensile strength of 3D printed tensile bars of compositions (rPP-1 to rPP-4) of the present invention over individual polymer rPP and PBAT.

[0030] Figure 6 shows comparison graph of modulus of 3D printed tensile bars of compositions (rPP- 1 to rPP-4) of the present invention over individual polymer rPP and PBAT.

[0031] Figure 7 shows comparison graph of elongation break of 3D printed tensile bars of compositions (rPP- 1 to rPP-4) of the present invention over individual polymer rPP and PBAT.

[0032] Figure 8 shows comparison graph of residual weight at different temperature ranges of the compositions (rPP-1 to rPP4) of the present invention over individual polymer rPP and PBAT.

[0033] Figure 9 shows comparison graph of derivative weight loss at different temperature ranges of the compositions (rPPl to rPP4) of the present invention over individual polymer rPP and PBAT.

[0034] Figure 10A and 10B shows comparison graph of effects of heat flow onto the compositions (rPPl to rPP4) of the present invention over individual polymer rPP and PBAT.

[0035] Figure 11 shows comparison of scanning electron microscope (SEM) images of the compositions rPP-2 (B) and rPP-4 (C) of the present invention over individual polymer rPP (A). PT / 2025 / 14947

[0036] DETAILED DESCRIPTION OF THE INVENTION

[0037] Here, the atactic PP (aPP) covers irregular methyl group (CH3) arrangement; the isotactic PP (iPP) covers methyl groups (CH3) arranged on one side of the carbon chain; and syndiotactic PP (sPP) covers alternating methyl group (CH3) arrangement.

[0038] The term “compatibilizer” used herein means a substance which is added in the blend of immiscible polymers, in order to increase their solubility, reactivity and stability.

[0039] The term “flexible polymer” means a polymer which has a glass transition temperature below 45 °C.

[0040] The term “glass transition temperature” is generally defined as “the temperature at which an amorphous polymer changes from a hard / glassy state to a soft / leathery state, or vice versa”.

[0041] In an embodiment, the present invention provides a composition comprising: i. at least two polymers; and ii. a compatibilizer; wherein the at least two polymers comprises of polymer 1 and polymer 2; the polymer 1 is a polyolefin selected from polypropylene (PP), polyethylene (PE) or its blends and copolymers or post consumer recyclates of these polymers or combination thereof; the polymer 2 is a flexible polymer selected from poly(butylene adipate-co-terephthalate) (PBAT), polybutylene succinate, lactic acid-polyethylene glycol-lactic acid block co-polymer, thermoplastic polyurethane, polycaprolactone, polyethylene glycol or combination thereof; and wherein the compatibilizer is selected from maleic anhydride, maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene, grafted ethylene-propylene-diene monomer, thermoplastic elastomer, ethylene-methyl acrylate or combination thereof.

[0042] In an embodiment, the at least two polymers (polymer 1: polymer 2) in the composition (polymer 1: polymer 2) is present in a weight ratio ranging from 80:20 to 40:60. More preferably, the weight ratio of the at least two polymers is in a range from 80:20 to 60:40. In specific embodiment, the weight ratio of the at least two polymers in the composition is 80:20, 70:30, 60:40, 50:50 and 40:60. PT / 2025 / 14947

[0043] The polyolefin of the present invention is in the form of homopolymer, copolymer, linear polymer or branched polymer or blends.

[0044] Preferably, the composition comprising at least two polymer is polypropylene and poly(butylene adipate-co-terephthalate). The polypropylene is selected from but limited to isotactic PP, atactic PP (aPP), syndiotactic PP (sPP), commercial PP, waste or recycled PP (rPP) and the like.

[0045] The compatibilizer is present in a concentration ranging from 4 wt. % to 12 wt. % of total composition. More preferably, the compatibilizer is present in a concentration ranging from 5 wt. % to 10 wt. % of total composition. In specific embodiment, the concentration of compatibilizer is 5 wt. %, 6 wt. %, 7 wt. %, 8 wt. %, 9 wt. % and 10 wt. % of total composition.

[0046] The non-limiting examples of thermoplastic elastomer as compatibilizer includes thermoplastic polyolefins and thermoplastic vulcanizates. Non-limiting examples of thermoplastic elastomer include maleic anhydride-grafted polypropylene, maleic anhydride-grafted polyethylene, grafted ethylene-propylene-diene monomer.

[0047] The composition of the present invention when used for production of 3D printed articles exhibits reduced warpage and provides an article with better mechanical properties such as optimum roughness, lesser brittleness and improved elongation point for break.

[0048] The composition of the present invention when used for 3D printing provides an article having tensile strength (MPa) in a range from 10 to 19, elongation (%) at break in a range from 6 to 124, modulus (MPa) in a range of 570 to 890 and toughness (KJ / m3) in a range from 6.5 to 150.

[0049] Further when compared with composition comprising neat rPP or only propylene, the 3D printed article obtained from the composition of the present invention demonstrates reduction of warpage in a range from 45-85%, increase in elongation (%) at break in a range from 250 to 6500%, decrease in the modulus in a range from 40-62% and increase in toughness in a range from 240-7100%.

[0050] In another embodiment, the present invention provides a process for preparation of the composition of the present invention by melt mixing at least two polymers with a compatibilizer to obtain a blend in a twin screw extruder at a temperature in a range from PT / 2025 / 14947

[0051] 180°C-230 °C and at a speed in the range from 60 (rotations per minute) rpm to 120 rpm, for a time period in a range from 3 minutes to 30 minutes to obtain the composition. In another embodiment, the melt mixing is carried out at a temperature in a range from 180°C to 230°C for 3 to 7 minutes.

[0052] The process of the present invention is simple and does not involve use of toxic solvents or reagents.

[0053] In another embodiment, the composition of the present invention is useful for 3D printing specifically via Fused Filament Fabrication (FFF) 3D printing, to obtain article with better stability, lesser or without warpage and optimum mechanical properties.

[0054] In another embodiment, the present invention provides a process for preparing an article by 3D printing, the process comprising: a) feeding the composition of the present invention into a nozzle of the 3D printer; b) heating the build plate at a temperature in the range of 80-110 °C and the nozzle in the temperature range of 190-230°C; c) passing the composition through the heated nozzle; and d) extruding the heated composition from the nozzle with a printing speed in the range of 30 mm / sec to 70 mm / sec on the build plate to obtain the 3D printed article.

[0055] In an embodiment, the nozzle has a diameter in a range from 0.3 to 0.6 mm. Preferably, the nozzle has a diameter of 0.4 mm.

[0056] In the process of 3D printing, prior to the step of extruding the composition on the build plate, a polyvinyl alcohol (PVA)-based adhesive is applied to the surface of the build plate to enhance the adhesion of the extruded composition.

[0057] Preferably, the build plate is heated at a temperature in a range from 80°C to 100°C. More preferably, the build plate is heated at a temperature of 90°C.

[0058] The process of the present invention is simple and does not require any toxic solvents / reagents. PT / 2025 / 14947

[0059] Further, the article prepared by the process of the present invention can be used for automotive components, medical devices, soft robotics, electrical and electronic components etc.

[0060] EXAMPLES:

[0061] Locally sourced waste polypropylene-based micropipette tip boxes (rPP) are collected, sterilized, and shredded into 5-8 mm fragments. PBAT (Ecoworld®), obtained in granular form, features a flow rate index of <5 g / 10 min (190 °C, 2.16 kg), a melting temperature range of 95-135 °C, and a density of 1.24 ±0.02. This PBAT is purchased from Banka Bioloo Ind. Pvt. Ltd. Additionally, maleic anhydride grafted polypropylene (Polybond 3200) from Polybond India Pvt. Ltd. serves as a compatibilizer between PBAT and rPP. PVA based 3M Scotch Purple Glue Stick is purchased from 3M India Limited, Plot 48-51, Electronics City, Hosur Road, Bengaluru, Karnataka.

[0062] Example 1: Preparation of Compositions rPP-1 to rPP-5;

[0063] All the materials were vacuum dried overnight in an oven at 70 °C. The rPP and PBAT polymer pellets are blended by batch mixing at different weight % of rPP / PBAT ratios (80 / 20, 70 / 30, 60 / 40) with two different concentrations of MAPP (5 % and 10 %). The melt blending was carried out using Haake mini CTW twin screw extruder. The melt mixing was carried out at 215 °C for 5 min and the rotor speed was set at 80 rpm and the filament of diameter 2.85 ±0.05 mm. The details of the compositions are explained in Table 1:

[0064] Table 1: Compositions rPP-1 to rPP-5 (the at least two polymers cover combination of rPP and PBAT). PT / 2025 / 14947

[0065] Example 2: Production of article using compositions of Example 1 via 3D printing:

[0066] According to ASTM D 638, Type V dumbbell- shaped specimens of rPP and rPP / PBAT compositions of Example 1 with cross-section of 3.18 x 3.2 mm2and a gauge length of 7.62 mm were printed by Ultimaker 3 for mechanical characterization. While the specimen for warpage quantification was printed as shown in Figure 1. The printing parameter for 3D printing is listed in Table 2 below and the process of 3D printing is illustrated in Figure 1. The temperature of the room was maintained at 23 °C.

[0067] Printing bed adhesion: Polyvinyl alcohol-based glue was used for build plate adhesion (bed adhesion). Table 2: PT / 2025 / 14947

[0068] Example 3: Evaluation of 3D printed articles prepared according to Example 2

[0069] The 3D printed articles prepared according to Example 2 using compositions of Example 1 were tested for mechanical properties and warpage quantification, based on formula and Tables 3-4 provided below:

[0070] Formula: warpage height (h)

[0071] Warpage % = X 100 length of diagonal (d)

[0072] The results for warpage analysis are provided in Table 3 below:

[0073] Table 3: Warpage Analysis of 3D printed products PT / 2025 / 14947

[0074] As observed from Table 3, it is evident that the warpage of the compositions of the present invention (rPP-1 to rPP-4) is lesser than the neat rPP and PBAT polymers, making the compositions a suitable candidate for 3D printing to obtain articles with better resolution and lesser or negligible warpage. Further, Figure 2 demonstrates the image of 3D printed article 5 obtained from rPP (Comparative example A) and rPP-4 of the present invention. As observed, the 3D printed article obtained from the composition of the present invention restores the structures without any significant deformation as compared to Comparative Example A which shows curvy edges.

[0075] The compositions of the present inventions of Example 1 (rPP-1 to rPP4) were tested for their 10 tensile stress (Figure 3), toughness (Figure 4), tensile strength (Figure 5), modulus of elasticity (Figure 6) and elongation at break (Figure 7) in comparison to individual polymers rPP (comparative Example A) and PBAT (Comparative Example B). The results obtained are presented in Table 4 below.

[0076] Table 4: Mechanical properties of 3D printed tensile bars of various compositions PT / 2025 / 14947

[0077] Table 4 and Figure 3 demonstrate that rPP is inherently brittle, exhibiting very low elongation and toughness compared to PBAT. Whereas the composition of the present invention demonstrates an improved elongation and toughness without altering the overall properties of the 3D printed article.

[0078] 5 Further, the above Table 4 and Figure 4 demonstrate that rPP has a toughness of only 2 KJ / m’ 3. However, the composition of the present invention comprising rPP with PBAT and MAPP as compatibilizer demonstrates a superior toughness of up to 90 KJ / m3(rPP-4).

[0079] With regard to tensile strength, as observed from Table 4 and Figure 5, the compositions of the 0 present invention (rPP-1 to rPP-4) demonstrate an acceptable tensile strength without altering the overall properties of the 3D printed articles.

[0080] Table 4 and Figure 6 demonstrate that PBAT has the lowest modulus of elasticity, this is attributed to the flexible segments in PBAT's chemical structure that increase its flexibility, thereby reducing its modulus of elasticity. Whereas the compositions of the present invention demonstrate comparatively higher modulus of elasticity thereby suggesting its ability to resist deformation under stress and is suitability for load-bearing or structural applications.

[0081] With regard to elongation at break (Table 4 and Figure 7), rPP polymer (Comparative Example A) demonstrates a poor elongation at break. While the compositions of the present invention comprising a blend of rPP and PBAT with compatibilizer demonstrates a higher elongation at 5 break, suggesting the better flexibility of the 3D printed article. PT / 2025 / 14947

[0082] Overall, Table 4 suggests that rPP (Comparative Example A) alone exhibits brittle mechanical behavior characterized by low elongation at break and negligible toughness rendering it unsuitable for load bearing or impact-resistant 3D applications. In contrast, PBAT (Comparative Example B) demonstrates superior elongation and toughness but lacks stiffness and modulus thus limiting its utility as a structural material. Whereas the compositions of the present invention (rPP-1 to rPP-4) demonstrated an improved or acceptable mechanical performance without altering the overall property of the article. Among the compositions, rPP- 1 provided enhanced ductility and toughness without significant loss of tensile strength while rPP-4 demonstrated an optimal balance of the overall mechanical properties including improved modulus, toughness and elongation, making it suitable for applications requiring both durability and structural integrity. This proves that the compositions of the present invention give all desirable properties in a single article which the individual polymer fails to give (Comparative Example A and B).

[0083] Thermal and crystallization studies of 3D printed articles

[0084] Figure 8 demonstrates the comparison of residual weight at different temperatures for the 3D printed objects compositions rPP-1 to rPP-4 of the present invention over Comparative Example A (r-PP) and Comparative Example B (PBAT). This graph shows onset degradation of various samples. PBAT degrades at a lower temperature as compared to the rPP, suggesting its lower thermal stability. The results show that rPP and PBAT have single step degradation. Whereas the compositions of the present invention show two stage degradation, first step corresponds to PBAT, while second step corresponds to rPP degradation. Almost all the prepared compositions have onset degradation temperatures in between PBAT and rPP.

[0085] Figure 9 shows comparison graph of derivative weight loss at different temperature ranges of the compositions (rPPl to rPP4) of the present invention over individual polymer rPP and PBAT. The results show rPP & PBAT have single-step degradation. PBAT degrades at lower temperatures compared to rPP. However, the graph shows two different peaks for all rPP compositions.

[0086] Further, both, Figures 8 and 9 suggests that amongst the compositions, rPP-4 demonstrates a higher degradation temperature, suggesting its better thermal stability.

[0087] Figure 10A and 10B shows comparison graph of effects of heat flow onto the compositions (rPPl to rPP4) of the present invention over individual polymer rPP and PBAT. Both graphs PT / 2025 / 14947 are DSC plots where 10A depicts crystallization temperature, and 10B depicts melting temperature. Non-isothermal DSC has been carried out to analyse the change in crystallisation and melting temperature of the compositions. The result shows that crystallisation temperature (Tc) of the compositions of the present invention is lower than rPP. Similarly, the melting peaks are also slightly reduced as compared to rPP.

[0088] Figure 11 shows comparison of scanning electron microscope (SEM) images of the compositions rPP-2 (B) and rPP-4 (C) of the present invention over individual polymer rPP (A). The images show rPP as a continuous phase system while rPP-2 & rPP-4 have two phases where PBAT is dispersed in rPP. The results show that rPP-4 has more homogeneous dispersion of PBAT. The homogenous dispersion helps to achieve enhanced mechanical properties like strength, elongation at break and toughness for rPP4.

[0089] ADVANTAGES OF THE INVENTION:

[0090] • It provides the compositions and 3D printed products with better stability, lesser or without warpage and optimum mechanical properties with lower cost of materials.

[0091] • It provides the compositions with elongation at break point increased up to 6500% when compared to neat rPP.

[0092] • It provides the compositions with toughness increased up to 7100% when compared to neat rPP.

[0093] It provides the compositions with lesser warpage of around 11.1 % & 7.8 % when compared to neat rPP having 25% warpage.

Claims

PT / 2025 / 14947WE CLAIM:

1. A composition comprising: i. at least two polymers; and ii. a compatibilizer; wherein the at least two polymers comprises of polymer 1 and polymer 2; the polymer 1 is a polyolefin selected from polypropylene (PP), polyethylene (PE) or combination thereof; the polymer 2 is a flexible polymer selected from poly(butylene adipate-co-terephthalate) (PBAT), polybutylene succinate, lactic acid-polyethylene glycol-lactic acid block copolymer, thermoplastic polyurethane, polycaprolactone, polyethylene glycol or combination thereof; and wherein the compatibilizer is selected from maleic anhydride, maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene, grafted ethylene-propylene-diene monomer, thermoplastic elastomer, ethylene-methyl acrylate or combination thereof.

2. The composition as claimed in claim 1, wherein the at least two polymers is present in a weight ratio ranging from 80:20 to 40:60.

3. The composition as claimed in claim 1, wherein polyolefin is in the form of homopolymer, copolymer, linear polymer or branched polymer.

4. The process as claimed in claim 1, wherein the compatibilizer is present in a concentration ranging from 4 wt. % to 12 wt. % of total composition.

5. The process as claimed in claim 1, wherein the thermoplastic elastomer as compatibilizer includes thermoplastic polyolefin and thermoplastic vulcanizates.

6. A process for preparation of the composition as claimed in claim 1, by melt mixing at least two polymers with a compatibilizer to obtain a blend in a twin screw extruder at a temperature in a range from 180°C-230 °C and at a speed in a range from 60 rpm (rotations per minute) to 120 rpm, for a time period in a range from 3 minutes to 30 minutes to obtain the composition.PT / 2025 / 149477. A process for preparing an article by 3D printing, the process comprising: a) feeding the composition as claimed in claim 1 into a nozzle of the 3D printer; b) heating the build plate at a temperature in the range of 80-110 °C and the nozzle in the temperature range of 180-230°C; c) passing the composition through the heated nozzle; and d) extruding the heated composition from the nozzle with a printing speed in the range of 30 mm / sec to 70 mm / sec on the build plate to obtain the 3D printed article.

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