The Influence of Monomer Structure on the Properties of Ionogels Obtained by Thiol–Ene Photopolymerization

The influence of ene and thiol monomer structure on the mechanical and electrochemical properties of thiol–ene polymeric ionogels were investigated. Ionogels were obtained in situ by thiol–ene photopolymerization of 1,3,5-triallyl-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (TATT), 2,4,6-triallyloxy-1,3,5-triazine (TAT), diallyl phthalate (DAP), and glyoxal bis(diallyl acetal) (GBDA) used as enes and trimethylolpropane tris(3-mercaptopropionate) (TMPTP), pentaerythritol tetrakis(3-mercaptopropionate) (PETMP), and pentaerythritol tetrakis(3-mercaptobutyrate) (PETMB) used as thiols in 70 wt.% of ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMImNTf2). The mechanical strength of ionogels was studied by puncture resistance and ionic conductivity by electrochemical impedance spectroscopy. The course of photopolymerization by photo-DSC method (differential scanning calorimetry) as well as characterization of compositions and its components (by IR and UV spectroscopy-Kamlet–Taft parameters) were also studied. The resulting ionogels were opaque, with phase separation, which resulted from the dispersion mechanism of polymerization. The mechanical and conductive properties of the obtained materials were found to be largely dependent on the monomer structure. Ionogels based on triazine monomers TAT and TATT were characterized by higher mechanical strength, while those based on aliphatic GBDA had the highest conductivity. These parameters are strongly related to the structure of the polymer matrix, which is in the form of connected spheres. The conductivity of ionogels was high, in the range of 3.5–5.1 mS∙cm−1.

Self-Healing UV-Curable Acrylate Coatings for Wood Finishing System, Part 2: Impact of Monomer Structure and Self-Healing Parameters on Self-Healing Efficiency

Wood is increasingly used in construction for the benefits it brings to occupants and for its ecological aspect. Indoor wood products are frequently subject to mechanical aggressions, their abrasion and scratch resistance thus need to be improved. The coating system ensures the wood surface protection, which is, for wood flooring, a multilayer acrylate UV-curable 100% solid system. To increase the service life of wood flooring, a new property is studied: self-healing. The objective of this study is to observe the impact of monomer structure on self-healing efficiency and the effect of self-healing parameters. A previous formulation was developed using hydrogen bond technology to generate the self-healing property. In this paper, the assessment of the formulation and the self-healing parameters’ impact on self-healing efficiency as well as the physicochemical properties are presented. The composition of the monomer part in the formulations was varied, and the effect on the conversion yield (measured by FT-IR), on the Tg and crosslinking density (measured by DMA) and on mechanical resistance (evaluated via hardness pendulum, indentation, and reverse impact) was analyzed. The self-healing efficiency of the coatings was determined by gloss and scratch depth measurements (under constant and progressive load). It was proven that monomers with three acrylate functions bring too much crosslinking, which inhibits the chain mobility necessary to observe self-healing. The presence of the AHPMA monomer in the formulation permits considerably increasing the crosslinking density (CLD) while keeping good self-healing efficiency. It was also observed that the self-healing behavior of the coatings is different according to the damage caused. Indeed, the self-healing results after abrasion and after scratch (under constant or progressive load) are different. In conclusion, it is possible to increase CLD while keeping self-healing behavior until a certain limit and with a linear monomer structure to avoid steric hindrance. Moreover, the selection of the best coatings (the one with the highest self-healing) depends on the damage.

Thermal and Mechanical Characterisation of Poly(ω -Hydroxy Pelargonate): A Preliminary Study for Bioplastic

Poly(ω-hydroxy pelargonate) or P(ω-OHP) is a potential biodegradable plastic which was prepared by melt condensation of its monomer (ω-hydroxy pelargonic acid). In this study, the performances of P(ω-OHP) in thermal and mechanical aspects, as well as the method employed for the monomer preparation was presented. Although this type of monomer is well established for pharmaceutical and cosmetic application, its possibility to be applied in bioplastic has not been extensively studied. Previous research also showed that the monomer preparation was rather complicated, expansive, and hazardous. Thus, this study offers the safe method through chemical modification which conducted in mild condition. The monomer structure was verified by using ESI-MS at 173.1 m/z with 92% purity. After melt-condensation process was carried out at 190 °C for 4 h, the formation of P(ω-OHP) was identified by the present of methylene ester bond indicated on 1H NMR peak at 4.05 ppm. The thermal properties were analyzed by DSC, TGA,and rheometer. P(ω-OHP) was melted at 72.8 °C and start to degrade at 220 °C with rheology analysis represented Newtonian flow at 80 and 180 °C.P(ω-OHP) contains 73.5% degree of crystallinity as determined by XRD with fewer amorphous area has affecting low mechanical value in hardness (31) and compressive strength (modulus 47.3 MPa, yield 1.03 MPa). The results suggest that P(ω-OHP) is thermally stable and physically hard and brittle. The findings have implications for bioplastic custom and subjected to improvement via polymer blending or block co-polymerization for application flexibility.

The Influences of Monomer Structure and Solvent on the Radical Copolymerization of Tertiary Amine and PEGylated Methacrylates

Tertiary Amine Methacrylates (TAMAs), such as 2-(N,N-diethylamino)ethyl methacrylate (DEAEMA) and 2-(N,N-dimethylamino)ethyl methacrylate (DMAEMA), and PEGylated (macro)monomers, such as 2-ethoxyethyl methacrylate (EEMA1) and poly(ethylene glycol) methyl ether methacrylates with 9 and...

Laboratory Optimization Study of Sulfonation Reaction toward Lignin Isolated from Bagasse

Bagasse is scientifically defined as waste from the extraction of sugarcane liquid after the grinding process. Bagasse is biomass which is used as raw material to be processed into surfactants. Bagasse fiber cannot be dissolved in water because it consists mostly of cellulose, pentosane and lignin. The optimum conditions for obtaining the highest yield and the best conversion of bagasse to lignin were achieved when used 80 mesh bagasse and 3 M NaOH as a hydrolysis agent. Then lignin is reacted with 0.25 sodium bisulfite to the surfactant sodium lignosulfonate. Lignin and sodium lignosulfonate were further characterized using a FTIR spectrophotometer to determine the components contained therein. The lignin component consists of phenolic functional group elements, aliphatic and aromatic groups, ketone groups, aren functional groups, amine groups and alkyl groups along with standard lignin components. Likewise with lignosulfonates, with indicator components consisting of C═C alkenes, Sulfate S═O, C═O carboxylic acids and S-OR esters. The NMR test was resulted the monomer structure of SLS surfactant bagasse. The results indicate that the lignin isolation process from bagasse has been successfully. Likewise, the sulfonation of lignin to lignosulfonate is also successful.