Bio-based Acrylate Research Articles

Valorizing Biopolyester Suberin: Modification of Cellulose Nanocrystals and Performance Assessment in 3D-Printed Biobased Acrylates.

Suberin, a common biomass processing waste, is a complex biopolymer and a promising source for the biorefinery of chemicals. Six different approaches for the extraction of birch outer bark suberin fatty acids (SFAs) were explored, and their application in grafting the surface of cellulose nanocrystals (CNCs) was investigated. Successful CNC functionalization was controlled with FTIR and NMR analyses. In-depth research allowed us to evaluate the interface of the nanocellulose and polymer matrix. Three structurally distinct SFA-grafted CNCs were integrated into a vegetable oil-based acrylate resin in an ultralow concentration of 0.1 wt %. Five biobased acrylic resin formulations were prepared: without reinforcement, with CNC, and with three distinct SFA-grafted CNCs. Vat photopolymerization (VP) 3D printing was utilized for sample preparation. The effects of grafted CNC components on 3D-printed samples' thermal stability, thermomechanical properties, and wettability were evaluated in detail. CNC functionalization enhanced the interface with the polymer matrix, yielding up to a 2-fold increase in elongation and up to a 2.5-fold increase in strength in tensile and flexural tests compared to the polymeric matrix. The CNC-SFA-modified filler demonstrated performance comparable to, or even better than, petroleum-based chemical modification routes found in the existing literature. This study highlights a promising approach for green functionalization of CNCs and verifies its use in interface enhancement using a biobased acrylate matrix.

Surface modification strategies for improved cellulose nanocrystal integration in 3D-Printed bio-based acrylate matrix

The current application of renewable resources in vat photopolymerization (VP) 3D printing is rather limited, emphasizing the importance of incorporating bio-based materials into additive manufacturing (AM). In this study, VP 3D printing technology was applied to create composites (derived from soybean oil-based resin) reinforced with cellulose nanocrystals (CNC). Two distinct modifications for CNC, i.e., the acrylation and functionalization with methyl methacrylate, were selected to achieve strong bonding with the UV-curable acrylate matrix. With the use of 0.1 wt% of modified CNC, the resins retain remarkable performance and support the creation of high-resolution prints. The successful integration of modified CNC showed significant improvements in tensile and flexural properties, e.g., elongation at break increased by 75 % and 295 %, respectively. The addition of modified CNC fillers also increased tensile strength by 147 % and flexural strength by 121 %. Fourier-transformation infrared (FTIR) spectroscopy and dynamic mechanical analysis (DMA) testified to the enhanced interface between filler and matrix. The morphological features and print quality were examined with microscopic analysis, UV-VIS spectroscopy, and colorimetry. The resin showed exceptional printing resolution, characteristic of VP printing, and yielded double bond conversion rates greater than 70 %. The findings presented here indicate that the addition of 0.1 wt% of modified CNC to bio-based resins results in an exceptional increase in the mechanical performance and dimensional stability of printed materials.

An easy-to-build, accessible volumetric 3D printer based on a liquid crystal display for rapid resin development

Additive manufacturing has revolutionized the way prototypes and one-off parts are produced, but standard additive manufacturing techniques such as material extrusion or vat photopolymerization still present various issues like high print times and defects due to the layer-by-layer nature of the print process. Computed axial lithography (CAL), a novel volumetric additive manufacturing technique, solves many of the issues associated with traditional 3D printing, like staircasing defects and long printing times. However, state of the art CAL requires complex optical setups, limiting access to a working machine, greatly reducing the pace of new material and technologies being adapted to CAL. The Liquid Crystal Display-based computed axial lithography (LCD-CAL) setup here presented keeps many of the advantages of CAL, but utilizes a single lens and an LCD for its optical setup. By moving to LCDs, the machine cost is greatly reduced, and the extremely simplified optical setup of LCD-CAL makes CAL widely accessible. To highlight the versatility of the developed LCD-CAL, we design and characterize two high-viscosity resins for CAL printing based on highly crosslinked and bio-based acrylates, respectively. This work paves the way for widespread adoption of volumetric 3D printing by making a low cost, high speed CAL printer available.

Waterborne polymers and coatings from bio-based butenolides.

In the quest for sustainable paints and coatings, bio-based resources for the polymeric binder constituents are key. Recently, we introduced poly-butenolides as bio-based acrylate replacement for solventborne and 100% solids (UV-curing) coatings. Here, we report the first step towards aqueous poly-butenolide dispersions, enabling the use of this novel binder technology platform in waterborne coatings.

UV-Cured Bio-Based Acrylated Soybean Oil Scaffold Reinforced with Bioactive Glasses.

In this study, a bio-based acrylate resin derived from soybean oil was used in combination with a reactive diluent, isobornyl acrylate, to synthetize a composite scaffold reinforced with bioactive glass particles. The formulation contained acrylated epoxidized soybean oil (AESO), isobornyl acrylate (IBOA), a photo-initiator (Irgacure 819) and a bioactive glass particle. The resin showed high reactivity towards radical photopolymerisation, and the presence of the bioactive glass did not significantly affect the photocuring process. The 3D-printed samples showed different properties from the mould-polymerised samples. The glass transition temperature Tg showed an increase of 3D samples with increasing bioactive glass content, attributed to the layer-by-layer curing process that resulted in improved interaction between the bioactive glass and the polymer matrix. Scanning electron microscope analysis revealed an optimal distribution on bioactive glass within the samples. Compression tests indicated that the 3D-printed sample exhibited higher modulus compared to mould-synthetized samples, proving the enhanced mechanical behaviour of 3D-printed scaffolds. The cytocompatibility and biocompatibility of the samples were evaluated using human bone marrow mesenchymal stem cells (bMSCs). The metabolic activity and attachment of cells on the samples' surfaces were analysed, and the results demonstrated higher metabolic activity and increased cell attachment on the surfaces containing higher bioactive glass content. The viability of the cells was further confirmed through live/dead staining and reseeding experiments. Overall, this study presents a novel approach for fabricating bioactive glass reinforced scaffolds using 3D printing technology, offering potential applications in tissue engineering.

Analysis of bio-based acrylate accelerated weathering: A study of nanocellulose impact on the bulk durability of 3D-printed nanocomposites

Bio-based resins for UV-assisted photopolymerization vat 3D printing have received immense research interest. 3D printing has initiated the 4.0 industrial revolution and is expected to squeeze in more production industries, including making materials for outdoor applications. Weathering investigations have been devoted mainly to fossil acrylic polymers. This research aims to close the gap in understanding bio-based acrylic 3D-printed polymer weathering performance. QUV accelerated weathering was used on vegetable oil-based 3D-printed compositions with nanofibrillated cellulose (NFC) as reinforcing filler. Discoloration, cracking, FTIR measurements of surface chemical degradation, and bulk properties evaluated by changes in mechanical performance were used to characterize materials performance during weathering. NFC reinforcement delays the yellowing and cracking during 1000 h of weathering. After weathering, increased flexural stress and strain were achieved with 0.5 wt% NFC loading. Chemical analysis reveals simultaneous photocleavage and additional crosslinking of the macromolecular chains. The glass transition temperature increased by up to 20 °C. NFC introduction in bio-based polymers increased of weathering endurance and mechanical performance. The NFC is compatible with and a perspective filler in bio-based acrylic resins for 3D printing applications.

Biobased Acrylate Shells for Microcapsules Used in Self-Healing of Cementitious Materials

To facilitate the ongoing transition towards carbon neutrality, the use of renewable materials for additive manufacturing has become increasingly important. Here, we report for the first time the fabrication of microcapsules from biobased acrylate shells using microfluidics. To select the shell, a wide range of biobased acrylates disclosed in the literature was considered according to their tensile strength, ductile transition temperature and global availability. Once acrylate epoxidised soybean oil (AESO) was selected, its viscosity was adjusted to valuables suitable for the microfluidic device using two different diluting agents. Double emulsions were successfully produced using microfluidics, followed by photopolymerisation of the shell and characterisation of the capsules. Microcapsules containing AESO and isobornyl acrylate (IBOA) were produced with an outer diameter ~490 μm, shell thickness ranging between 36 and 67 μm, and production rates around 2.4 g/h. The mechanical properties of the shell were characterised as tensile strength of 29.2 ± 7.7 MPa, Young’s modulus of 1.7 ± 0.4 GPa and the ductile transition temperature was estimated as 42 °C. To investigate physical triggering, microcapsules produced with a size of 481 ± 4 μm and with a measured shell thickness around 6 μm were embedded in the cementitious matrix. The triggered shells were observed with scanning electron microscopy (SEM) and the uniform distribution of the capsules in cement paste was confirmed using X-ray computed tomography (XCT). These advances can facilitate the wide application of biobased resins for the fabrication of microcapsules for self-healing in cementitious materials.

Influence of UV curing parameters for bio-based versus fossil-based acrylates in mechanical abrasion

Influence of UV curing parameters for bio-based versus fossil-based acrylates in mechanical abrasion

Emergence of Polymeric Material Utilising Sustainable Radiation Curable Palm Oil-Based Products for Advanced Technology Applications.

In countries that are rich with oil palm, the use of palm oil to produce bio-based acrylates and polyol can be the most eminent raw materials used for developing new and advanced natural polymeric materials involving radiation technique, like coating resins, nanoparticles, scaffold, nanocomposites, and lithography for different branches of the industry. The presence of hydrocarbon chains, carbon double bonds, and ester bonds in palm oil allows it to open up the possibility of fine-tuning its unique structures in the development of novel materials. Cross-linking, reversible addition-fragmentation chain transfer (RAFT), polymerization, grafting, and degradation are among the radiation mechanisms triggered by gamma, electron beam, ultraviolet, or laser irradiation sources. These radiation techniques are widely used in the development of polymeric materials because they are considered as the most versatile, inexpensive, easy, and effective methods. Therefore, this review summarized and emphasized on several recent studies that have reported on emerging radiation processing technologies for the production of radiation curable palm oil-based polymeric materials with a promising future in certain industries and biomedical applications. This review also discusses the rich potential of biopolymeric materials for advanced technology applications.

Production and Polymerization of Biobased Acrylates and Analogs.

To prepare biobased polymers, particular attention must be paid to the obtention of the monomers from which they are derived. (Meth)acrylates and their analogs constitute such a class of monomers that have been extensively studied due to the wide range of polymers accessible from them. This review therefore aims to highlight the progresses made in the production and polymerization of (meth)acrylates and their analogs. Acrylic acid production from biomass is close to commercialization, as three different high-potential intermediates are identified: glycerol, lactic acid, and 3-hydroxypropionic acid. Biobased methacrylic acid is less common, but several promising options are available, such as the decarboxylation of itaconic acid or the dehydration of 2-hydroxyisobutyric acid. Itaconic acid is also a vinylic monomer of great interest, and polymers derived from it have already found commercial applications. Methylene butyrolactones are promising monomers, obtained from bioresources via three different intermediates: levulinic, succinic, or itaconic acid. Although expensive, methylene butyrolactones have a strong potential for the production of high-performance polymers. Finally, β-substituted acrylic monomers, such as cinnamic, fumaric, muconic, or crotonic acid, are also examined, as they provide an original access to biobased materials from various renewable raw materials, such as protein waste, lignin, or wastewater.

Synthesis and Properties of Thermosets from Tung Oil and Furfuryl Methacrylate.

This work focuses on the development of cross-linked polymer from a highly unsaturated vegetable oil, tung oil (TO) and a bio-based acrylate, furfuryl methacrylate (FMA). The presence of a high degree of unsaturated carbon-carbon bonding in TO makes it a suitable precursor for polymer synthesis. Using this advantage of TO, in this work, we have synthesised a cross-linked polymer from TO and FMA through free radical polymerisation followed by Diels–Alder (DA) reaction. Successful incorporation of both of the raw materials and the two chemical reactions was shown using Fourier-transform infrared (FTIR) and Raman spectroscopy. The development of cross-linked structure was analysed through thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA).

Synthesis and polymerization of bio-based acrylates: a review

Acrylates and polyacrylates have been produced massively due to their interesting applications like Plexiglas.

Facile synthesis and characterization of novel multi-functional bio-based acrylate prepolymers derived from tung oil and its application in UV-curable coatings

With the growing depletion of fossil energy and the unceasing joint efforts to maintain sustainable development, bio-based materials are appealing for academic and industrial researchers because they possess the merits of environmental friendliness and renewability. In this study, a tung-oil-based derivative, tung-maleic anhydride (TMA), which was prepared from methyl eleostearate and maleic anhydride, reacted with epichlorohydrin to synthesize epoxidized tung-maleic anhydride (ETMA) after the hydrolysis of anhydride. Furthermore, ETMA was chemically modified by pentaerythritol triacrylate to obtain hexa-functional epoxidized tung-maleic anhydride acrylate prepolymers (PETMA). The chemical structure of the resultant prepolymers was confirmed by FT-IR and 1H NMR, while the rheological behavior of prepolymers was investigated by using a rheometer. Also, the curing efficiency of different photoinitiators on PETMA prepolymers was investigated, and the result revealed that the tung oil-based prepolymers could be rapidly cured with 3.0 wt% photoinitiator PI-819 under a UV lamp with 5 kW light intensity within 45 s. Furthermore, various reactive diluents were used to be cured with PETMA prepolymers, and the thermomechanical properties, mechanical properties, volume shrinkage, swelling property, and general performances of the resultant UV-cured films were investigated. DMA results revealed that, among the films cured by the reactive diluents with same functionality, reactive diluents with a higher Tg resulted in a higher Tg toward the resultant cured films. The crosslinking density (νe) of the films cured with various reactive diluents was determined by the double bond density, leading to the fact that the films cured with bi-functional reactive diluents exhibited a higher crosslinking density than the ones cured with mono-functional reactive diluents. TGA results showed that high crosslinking density facilitated improving the thermal stability of the cured films, while the steric structure in film matrix exerted adverse effect on thermal stability. Besides, tensile test indicated that high crosslinking density and steric structure facilitated the enhancement of mechanical properties toward the resultant films. More strikingly, all UV-cured films possessed excellent hardness, high glossiness and remarkable water resistance, and these high-performance bio-based UV-curable films are promising for widespread applications.

Highly functional bio-based acrylates with a hard core and soft arms: From synthesis to enhancement of an acrylated epoxidized soybean oil-based UV-curable coating

In the field of UV-curable resin, acrylated epoxidized soybean oil (AESO) is a crucial industrial bio-based acrylate, but it cannot be used alone owing to its poor thermal and mechanical properties. In this study, a series of highly functional acrylates containing a triazine ring as the rigid core and long fatty chains as soft arms were synthesized, these synthesized acrylates were then added to AESO to prepare UV-curable coating. The chemical structure and molecular weight of these acrylates were characterized through Fourier transform infrared spectroscopy, nuclear magnetic resonance, and gel permeation chromatography, and the curing behavior of the coating was studied using real-time infrared. The results of tensile testing, dynamic thermomechanical analysis and thermogravimetric analysis showed that the addition of highly functional acrylates significantly improved the thermal and mechanical properties of UV-cured films compared with pure AESO. In addition, the hardness of the AESO-based UV-cured coating was enhanced after the addition of highly functional bio-based acrylates. Compared with commercial petroleum-based acrylates with a similar structure, highly functional bio-based acrylates have a higher bio-based content and show more comprehensive performance.

Design of New Antifungal Dithiocarbamic Esters Having Bio-Based Acrylate Moiety

Nine new dithiocarbamic esters derived from bio-based acrylic acid were synthesized and evaluated for their in vitro antifungal activity against the phytopathogenic fungus Fusarium solani and fungi-like oomycete Phytophthora infestans. Among these nine dithiocarbamic derivatives, compound 6 (tert-butyl 3-(N,N-diethyldithiocarbamoyl)-propanoate) showed interesting antifungal efficacy at low concentration compared to the other tested dithiocarbamates. The structure–antifungal activity relationship of these designed dithiocarbamic esters is discussed.

Muconic acid esters as bio-based acrylate mimics

Dialkyl muconates are synthesized from biobased muconic acid. These monomers are shown to be readily polymerized in radical polymerizations, and may serve as alternatives to classical acrylates.

Synthesis and properties of UV-curable cardanol-based acrylate oligomers with cyclotriphosphazene core

Multiarm cardanol-based oligomers with a cyclotriphosphazene core were prepared through a nucleophilic substitution reaction; the structures of oligomers were fully characterized and confirmed through Fourier transfer infrared spectrometry, 1H nuclear magnetic resonance (NMR), 31P NMR, and gel permeation chromatography. The designed multiarm bio-based acrylates (AECC) were successfully prepared by epoxidizing the unsaturated aliphatic chain of cardanol segments with m-chloroperoxybenzoic acid and acrylating epoxy groups. The synthesized oligomers contain rigid phosphazene/benzene rings as “hard cores” and long aliphatic chains as “flexible shells.” Compared with commercial hyperbranched polyurethane acrylate (CN2302) and acrylated epoxidized soybean oil, cured AECC coatings and films exhibited not only greater hardness, excellent adhesion, higher glass transition temperatures, and excellent mechanical properties but also good thermal stability and biodegradability. We successfully obtained a high-performance UV-curing resin that has a high biorenewable material content and can meet basic daily requirements.

Cardanol modified fatty acids from camelina oils for flexible bio-based acrylates coatings

Novel bio-based acrylate was designed through the epoxy ring-opening reaction of cardanol glycidyl ether (CGE) with fatty acids from camelina oil (FACO), followed by epoxidation of unsaturated chains and then acrylation of the epoxides. Cardanol- and camelina oil-based acrylates were also respectively synthesized for comparison purposes. The bio-based acrylate coatings were then produced under UV-radiation from the acrylates monomers with an addition of a photoinitiator. Polymerization of the acrylates and synthesis of the monomers were observed using Fourier transform infrared (FTIR) spectroscopy, and the chemical structures and acryl contents of the acrylates were confirmed by proton nuclear magnetic resonance (1H NMR). The mechanical and thermal properties of the cured acrylates were evaluated using tensile test, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA). Observation of resistances to water, solvent, and hydrolytic degradation were conducted to water and toluene uptake test, methyl ethyl ketone (MEK) rub test, and a degradation test under sodium hydroxide solution. Gel content was measured to evaluate performance of the coatings, and other coating performances including gloss, adhesion, and pencil hardness were determined using the wood panel coated with the cured acrylates. Compared to acrylated epoxidized soybean oil (AESO) coating, the acrylate derived from the cardanol modified fatty acids showed higher tensile strength, hardness, glass transition temperature, thermal decomposition temperature at maximum degradation rate, and resistances to solvent and hydrolytic condition of the cured coating. Therefore, the newly designed acrylate is a great alternative to AESO.

Biobased Acrylate Photocurable Resin Formulation for Stereolithography 3D Printing

To facilitate the ongoing transition toward a circular economy, the availability of renewable materials for additive manufacturing becomes increasingly important. Here, we report the successful fabrication of complex shaped prototypes from biobased acrylate photopolymer resins, employing a commercial stereolithography apparatus (SLA) 3D printer. Four distinct resins with a biobased content ranging from 34 to 67% have been developed. All formulations demonstrated adequate viscosity and were readily polymerizable by the UV-laser-based SLA process. Increasing the double-bond concentration within the resin results in stiff and thermally resilient 3D printed products. High-viscosity resins lead to high-resolution prototypes with a complex microarchitecture and excellent surface finishing, comparable to commercial nonrenewable resins. These advances can facilitate the wide application of biobased resins for construction of new sustainable products via stereolithographic 3D printing methods.

HMF derivatives as platform molecules: aqueous Baylis–Hillman reaction of glucosyloxymethyl-furfural towards new biobased acrylates

A new type of biobased acrylates has been synthesized by a Baylis–Hillman reaction of alkylacrylates with α-D-glucosyloxymethyl-furfural (α-GMF), available in one step from isomaltulose. The reaction, performed in aqueous medium, was extended to other α,β-unsaturated substrates. The use of dimethylisosorbide as co-solvent was investigated.