01589nas a2200205 4500008004100000022001400041245010200055210006900157260000800226490000800234520086200242653001601104653002801120653002901148653001401177653002701191100001601218700001701234856013201251 2022 eng d a1022-135200aBiodegradable, solvent-free photocrosslinkable PLLA resin formulations for additive manufacturing0 aBiodegradable solventfree photocrosslinkable PLLA resin formulat cNOV0 v2233 a

Acrylate end-functionalized linear and star poly l-lactide (PLLA) based aliphatic, photocurable oligomeric crosslinkers are developed, which are formulated with hydroxyl (ethyl)methacrylate (HEMA) as a biodegradable reactive diluent to demonstrate successful application for solvent-less 3D printing using digital light processing (DLP) technique as well as a custom-designed direct ink writing 3D printer. The resin formulation for 3D printing is optimized using spot curing, photodifferential scanning calorimetry and cure depth analysis. The 3D printed parts exhibit promising mechanical property along with improved hydrophilicity and biodegradability. The development of new photocurable resin formulations are expected to meet the growing demand for raw materials that can be applied for developing custom designed bio implantable objects.

10a3D printing10abiodegradable materials10adigital light processing10aL-Lactide10aphotocurable materials1 aPal, Shibam1 aAsha, S., K. uhttps://library.ncl.res.in/content/biodegradable-solvent-free-photocrosslinkable-plla-resin-formulations-additive-manufacturing02603nas a2200229 4500008004100000022001400041245017500055210006900230260000900299300001100308490000800319520175500327653001602082653001602098653002802114653001802142653001702160100002302177700002802200700001702228856012802245 2023 eng d a0032-386100aDesign and synthesis of photocrosslinker and light blocker based on L-Amino acid polyester and their application in solvent-free resin formulation for DLP/SLA 3D printing0 aDesign and synthesis of photocrosslinker and light blocker based cMAR  a1257810 v2703 a

Customising material design for new technological applications like additive manufacturing (AM) is a challenging yet promising approach to create a palette of materials suitable for developing eco-friendly products. LGlutamic acid and L-aspartic acid based aliphatic, photocurable polyester crosslinkers were designed and developed and incorporated into a solvent-free photocurable resin formulation with hydroxyl (ethyl)methacrylate (HEMA). Proof-of-concept 3D printing of clear and transparent objects was demonstrated using digital light processing (DLP) and Stereolithography (SLA) techniques. Resolution of the 3D printed objects could be improved by incorporating a Dansyl labelled L-glutamic acid polyester, which not only aided in modulating the viscosity of the resin formulation but could also function as a light blocker, thereby avoiding polymerization of unwanted areas while 3D printing. The curing kinetics of the photocurable formulation was analyzed using photo differential Scanning Calorimetry. Enzymatic degradability studies of 3D printed films were undertaken in PBS buffer containing esterase enzyme and compared with 3D printed samples using HEMA and a commercial crosslinker (Trimethylolpropane triacrylate (TMPTA)). Scanning electron microscopy (SEM) was used to evaluate the morphology of the 3D printed films before and after enzymatic degradation in the PBS buffer for 60 days. The 3D printed amino acid crosslinked films of HEMA presented high degree of degradation in contrast to the near total absence of any degradation in the 3D printed film crosslinked using TMPTA. The availability of new photocurable formulations that are enzymatically degradable are highly sought after for 3D printing applications.

10a3D printing10aCrosslinker10aL -Amino acid Polyester10aLight blocker10aPhotocurable1 aKamble, Ganesh, N.1 aJoshi, Dheeraj, Chandra1 aAsha, S., K. uhttps://library.ncl.res.in/content/design-and-synthesis-photocrosslinker-and-light-blocker-based-l-amino-acid-polyester-and02168nas a2200205 4500008004100000022001400041245011400055210006900169260000900238490000800247520143600255653001601691653001601707653002901723653003401752653001401786100001601800700001701816856012901833 2024 eng d a0014-305700aThiol-ene-based degradable 3D printed network from bio resource derived monomers ethyl-lactate and isosorbide0 aThiolenebased degradable 3D printed network from bio resource de cFEB 0 v2053 a

A polymeric ene-based thiol-ene network is reported that was demonstrated for light-based 3D printing. Allyl poly (acrylate ethyl lactate) (PAEL) was synthesized starting from ethyl lactate in an efficient and scalable manner. Ethyl lactate is a biobased material obtained naturally or chemically in high yields in the form of ethyl ester of lactic acid. Isosorbide, which is also a bio based resource was converted into thiol derivative and was used along with Pentaerythritol tetrakis(3-mercaptopropionate) (PETMP) as multifunctional thiol. The polymeric nature of the ene (i.e. PAEL) imparted exceptionally high mechanical properties like Young's modulus of 1.75 GPa as well as high thermal stability with a decomposition temperature (Td,10%) exceeding 350 C for all the networks studied. The properties could also be customized by fine tuning the type and stoichiometric ratio of the thiol crosslinked employed. For instance, the Young's modulus range from 1.75 GPa to 1.03 GPa and glass transition temperature range from 44 C to 54 C could be achieved. DLP 3D printing was used to demonstrate the printability of the resins with high resolution and structural fidelity. The study also highlights the basemediated rapid hydrolytic degradation efficiency of the 3D printed parts, demonstrating the applicability of these novel polymeric ene based thiol-ene for sustainable and eco-friendly 3D printable formulations.

10a3D printing10aDegradation10adigital light processing10aPoly (acrylate ethyl lactate)10aThiol-ene1 aPal, Shibam1 aAsha, S., K. uhttps://library.ncl.res.in/content/thiol-ene-based-degradable-3d-printed-network-bio-resource-derived-monomers-ethyl-lactate01999nas a2200229 4500008004100000022001400041245013200055210006900187260000800256490000700264520117100271653001601442653001501458653002701473653002601500653002201526100002301548700002801571700002701599700001701626856012601643 2025 eng d a1861-472800aCarbohydrate-based polyester and amino acid polyester photocrosslinker and their resin formulation for 3D printing applications0 aCarbohydratebased polyester and amino acid polyester photocrossl cJUN0 v203 a

Fully bio-based polyester was designed and synthesized using the carbohydrate-based diol 2,4:3,5-di-O-methylene-D-mannitol (Manx) and dimethyl ester of 2,3:4,5-di-O-methylene-galactaric acid (Galx). Photocurable resin formulations were prepared by incorporating up to 15 wt% of the carbohydrate polyester into hydroxyl ethyl methacrylate (HEMA) along with polyacrylamide crosslinker derived from L-glutamic acid. Complex 3D structures with good shape fidelity could be 3D printed using these novel polyester resin formulations. The incorporation of the carbohydrate polyester improved the glass transition temperature of the 3D-printed objects. Enzymatic erosion studies conducted using esterase enzyme revealed a higher degradation rate for the 3D-printed films containing the carbohydrate polyester. The hydrolytic degradation analysis conducted in both acidic and basic environments revealed that the 3D-printed polymer network exhibits stability and resilience in acidic conditions, while it undergoes complete degradation in basic conditions. This finding underscores the possibility of tailoring degradation processes under regulated circumstances.

10a3D printing10aAmino acid10aCarbohydrate polyester10aEnzymatic degradation10aResin formulation1 aKamble, Ganesh, N.1 aJoshi, Dheeraj, Chandra1 aGavhane, Utreshwar, A.1 aAsha, S., K. uhttps://library.ncl.res.in/content/carbohydrate-based-polyester-and-amino-acid-polyester-photocrosslinker-and-their-resin02231nas a2200229 4500008004100000022001400041245010100055210006900156260000900225300001200234490000600246520145100252653001601703653002501719653003101744653001901775653001301794100002301807700002201830700001701852856013201869 2026 eng d a2637-610500aRecyclable l-glutamic acid-based polyester schiff base cross-linker for 3D printing applications0 aRecyclable lglutamic acidbased polyester schiff base crosslinker cJAN  a641-6500 v83 a

An l-amino acid-based polyester Schiff base cross-linker was developed from amine-functionalized polyester and biobased methacrylate vanillin. Vanillin, one of the few biobased and aromatic compounds readily available on an industrial scale, has recently garnered significant attention from the polymer community. The l-amino acid-based polyester Schiff base cross-linker (P3) was synthesized by condensing the aldehyde group of methacrylate vanillin with the amine group of the l-glutamic acid polyester. This polymeric cross-linker was used in resin formulations consisting of isobornyl acrylate as a reactive diluent and diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide as the photoinitiator for digital light processing (DLP) three-dimensional (3D) printing. The resulting 3D-printed parts exhibited good mechanical properties, with a Young's modulus of 1.5 GPa, and high thermal stability, with a T max of 410 degrees C. The chemical degradability of the 3D-printed materials was demonstrated in a mixture of tetrahydrofuran and diethylene triamine (1:1) at 80 degrees C for 48 h. The reusability of the recovered resin was demonstrated by adding fresh methacrylate vanillin and photoinitiator, followed by 3D printing using a DLP 3D printer. The 3D-printed parts produced from the recycled resin retained substantial mechanical properties, with a Young's modulus of 1.39 GPa, and thermal stability, with a T max of 390 degrees C.

10a3D printing10achemical degradation10acovalent adaptable network10al-glutamicacid10aVanillin1 aKamble, Ganesh, N.1 aGhute, Aaditi, P.1 aAsha, S., K. uhttps://library.ncl.res.in/content/recyclable-l-glutamic-acid-based-polyester-schiff-base-cross-linker-3d-printing-applications02655nas a2200289 4500008004100000022001400041245008500055210006900140260000800209490000800217520171400225653001601939653003101955653002201986653001602008653001302024100002902037700002502066700001802091700002302109700002002132700002202152700002302174700003102197700001702228856012002245 2026 eng d a1022-135200aVanillin-based recyclable thermosets and their glass fiber reinforced composites0 aVanillinbased recyclable thermosets and their glass fiber reinfo cJAN0 v2273 a

The accumulation of end-of-life plastic materials and composite reinforcement waste materials has brought much attention to developing sustainable alternatives and their re-processability. Incorporating covalent adaptable networks (CANs) into the crosslinked network bridges the concept of reversibility into the otherwise conventional non-reversible networks. This study investigates the structure-property relation in two reversible hardener systems derived from vanillin using Schiff base chemistry. The ``CAN'' systems were synthesized by condensation of vanillin with two amines, 4,4'-oxydianiline and tris(2-aminoethyl)amine, respectively, to form Va_ODA and Va_TAEA. The epoxy thermosets exhibited glass transition temperatures (T-g) of 125 degrees C and 115 degrees C, respectively, for Va_ODA and Va_TAEA, which is superior to most reversible vanillin-based systems reported. The vitrimer-thermosets exhibited promising mechanical and thermal properties, and reshaping abilities as a function of applied temperatures, indicating the dynamic nature of linkages. Chemical degradability was demonstrated by heating to 80 degrees C for 12 h in aqueous acidic medium or excess amine. The fabricated glass fiber composites exhibited good mechanical properties with tensile strength of 361 MPa and degradability in acetic acid/water mixture with a fiber recovery of >98 %. The recovered glass fiber exhibited almost similar tensile strength as the virgin glass fiber, demonstrating its potential reusability. The epoxy vitrimers underwent mechanical reprocessing through hot-pressing, as well as chemical reprocessing via 3D printing and by regeneration of imine bonds to form an epoxy resin.

10a3D printing10acovalent adaptable network10are-processability10aSchiff base10aVanillin1 aVeetil, Ashwani, Puthiya1 aRavikumar, Aniruddha1 aRajput, Tejas1 aSingh, Aman, Kumar1 aThakur, Tamanna1 aKrishna, Abhijith1 aPol, Harshawardhan1 aShanmuganathan, Kadhiravan1 aAsha, S., K. uhttps://library.ncl.res.in/content/vanillin-based-recyclable-thermosets-and-their-glass-fiber-reinforced-composites