Thickening Supercritical CO₂ with π-Stacked Co-Polymers: Molecular Insights into the Role of Intermolecular Interaction

Vinyl Benzoate/Heptadecafluorodecyl acrylate (VBe/HFDA) co-polymers were synthesized and characterized as thickening agents for supercritical carbon dioxide (SC-CO₂). The solubility and thickening capability of the co-polymer samples in SC-CO₂ were evaluated by measuring cloud point pressure and relative viscosity. The molecular dynamics (MD) simulation for all atoms was employed to simulate the microscopic molecular behavior and the intermolecular interaction of co-polymer⁻CO₂ systems. We found that the introduction of VBe group decreased the polymer⁻CO₂ interaction and increased the polymer⁻polymer interaction, leading to a reduction in solubility of the co-polymers in SC-CO₂. However, the co-polymer could generate more effective inter-chain interaction and generate more viscosity enhancement compared to the Poly(Heptadecafluorodecyl) (PHFDA) homopolymer due to the driving force provided by π-π stacking of the VBe groups. The optimum molar ratio value for VBe in co-polymers for the viscosity enhancement of SC-CO₂ was found to be 0.33 in this work. The P(HFDA_0.67-co-VBe_0.33) was able to enhance the viscosity of SC-CO₂ by 438 times at 5 wt. %. Less VBe content would result in a lack of intermolecular interaction, although excessive VBe content would generate more intramolecular π-π stacking and less intermolecular π-π stacking. Both conditions reduce the thickening capability of the P(HFDA-co-VBe) co-polymer. This work presented the relationship between structure and performance of the co-polymers in SC-CO₂ by combining experiment and molecular simulations.

Understanding the Effect of the Dianhydride Structure on the Properties of Semiaromatic Polyimides Containing a Biobased Fatty Diamine

In this work we report the effect of the hard block dianhydride structure on the overall properties of partially biobased semiaromatic polyimides. For the study, four polyimides were synthesized using aliphatic fatty dimer diamine (DD1) as the soft block and four different commercially available aromatic dianhydrides as the hard block: 4,4'-(4,4'-isopropylidenediphenoxy) bis(phthalic anhydride) (BPADA), 4,4'-oxidiphthalic anhydride (ODPA), 4,4'-(Hexafluoroisopropylidene) diphthalic anhydride (6FDA), and 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA). The polymers synthesized were fully organo-soluble thermoplastic branched polyimides with glass transition temperatures close to room temperature. The detailed analysis took into account several aspects of the dianhydrides structure (planarity, rigidity, bridging group between the phtalimides, and electronic properties) and related them to the results obtained by differential scanning calorimetry, rheology, fluorescence and broadband dielectric spectroscopy. Moreover, the effects of physical parameters (crystallization and electronic interactions) on the relaxation behavior are discussed. Despite the presence of the bulky branched soft block given by the dimer diamine, all polyimides showed intermolecular charge transfer complexes, whose extent depends on the electronic properties of the dianhydride hard block. Furthermore, the results showed that polyimides containing flexible and bulky hard blocks turned out fully amorphous while the more rigid dianhydride (BPDA) led to a nanophase separated morphology with low degree of crystallinity resulting in constrained segmental relaxation with high effect on its mechanical response with the annealing time. This work represents the first detailed report on the development and characterization of polyimides based on a biobased fatty dimer diamine. The results highlight the potential of polymer property design by controlled engineering of the aromatic dianhydride blocks.

Highly efficient strategies toward sustainable monomers and polymers derived from fatty acids via tetramethylguanidine promoted esterification

Three efficient strategies were developed to transform fatty acids into mono-functional monomers and thermoplastic polymers by using 1,1,3,3-tetramethylguanidine promoted esterification.

Ring opening polymerization of macrolactones: high conversions and activities using an yttrium catalyst

The ring-opening polymerization of macrolactones (C₁₅–C₂₃) is reported using an yttrium catalyst which shows high rates and conversions in the production of long-chain aliphatic polyesters.

Challenging cyclopropanation reactions on non-activated double bonds of fatty esters

Cyclopropanation reactions in the chain of unsaturated fatty esters is a good strategy for the ready preparation of potential monomers for polymerization.

Castor Oil: Properties, Uses, and Optimization of Processing Parameters in Commercial Production

Castor oil, produced from castor beans, has long been considered to be of important commercial value primarily for the manufacturing of soaps, lubricants, and coatings, among others. Global castor oil production is concentrated primarily in a small geographic region of Gujarat in Western India. This region is favorable due to its labor-intensive cultivation method and subtropical climate conditions. Entrepreneurs and castor processors in the United States and South America also cultivate castor beans but are faced with the challenge of achieving high castor oil production efficiency, as well as obtaining the desired oil quality. In this manuscript, we provide a detailed analysis of novel processing methods involved in castor oil production. We discuss novel processing methods by explaining specific processing parameters involved in castor oil production.

Renewability is not Enough: Recent Advances in the Sustainable Synthesis of Biomass-Derived Monomers and Polymers

Taking advantage of the structural diversity of different biomass resources, recent efforts were directed towards the synthesis of renewable monomers and polymers, either for the substitution of petroleum-based resources or for the design of novel polymers. Not only the use of biomass, but also the development of sustainable chemical approaches is a crucial aspect for the production of sustainable materials. This review discusses the recent examples of chemical modifications and polymerizations of abundant biomass resources with a clear focus on the sustainability of the described processes. Topics such as synthetic methodology, catalysis, and development of new solvent systems or greener alternative reagents are addressed. The chemistry of vegetable oil derivatives, terpenes, lignin, carbohydrates, and sugar-based platform chemicals was selected to highlight the trends in the active field of a sustainable use of renewable resources.

Toughened aromatic poly-(decylene terephthalate) copolyesters with two renewable eugenol-based components via a random copolymerization method

We synthesized two series of poly-(decylene terephthalate) copolyesters toughened with two renewable eugenol-based components, and the best results belong to PDT80%M120% and PDT80%M220% copolyesters.

Crosslinkable polyesters based on monomers derived from renewable lignin

Crosslinked polyesters based on renewable resources have been successfully prepared, they have better tensile property and biodegradability.

Sustainable glucose-based block copolymers exhibit elastomeric and adhesive behavior

Herein, we present the direct modification of glucose, an abundant and inexpensive sugar molecule, to produce new sustainable and functional polymers.

Self-assembly of well-defined fatty acid based amphiphilic thermoresponsive random copolymers

Side-chain stearic acid containing thermoresponsive and crystalline random copolymers are synthesized via RAFT technique, which self-assembled to spherical micellar structures in aqueous solution depending on stearate content in the copolymer.

Synthesis and Characterization of Poly(urethane-ether azomethine) Fatty Amide Based Corrosion Resistant Coatings fromPongamia glabraOil: An Eco-Friendly Approach

A novel attempt has been made to incorporate azomethine group in the backbone of polyurethane etherPongamiaoil fatty amide. The overall reaction was carried out in different steps like preparation of N,N-bis(2-hydroxyethyl)Pongamia glabraoil fatty amide, poly(ether fatty amide), and poly(urethane-ether) fatty amide. The hydroxyl terminated Schiff base, ethane 1,2-di(azomethine) bisphenol, reacts with fatty amide diol and is further treated with toluylene 2,4-diisocynate (TDI) to form poly(urethane-ether azomethine) fatty amide (PUEAF). These synthesized resins were characterized by FT IR,1H NMR, and13C NMR spectroscopic techniques. Molecular weight of PUEAF resin was measured by gel permeation chromatography (GPC), coating was made on mild steel strips, and evaluating their physicochemical and physicomechanical analysis was carried out by standard methods. The PUEAF25 coating showed highest scratch hardness (2.5 kg), gloss (90) at 45°, pencil hardness (4H), and impact resistance (150 lb/inch). Atomic force microscopy (AFM) and differential scanning calorimetry (DSC)/thermogravimetric analysis (TGA) were used to determine the topography and thermal behavior of PUEAF. Corrosion studies of PUEAF coated mild steel were used in different corrosive media (3.5 wt% HCl, 5 wt% NaCl, and tap water) at room temperature using potentiodynamic polarization technique. The results of this study showed that PUEAF coatings exhibit good physicomechanical, anticorrosive properties and get application up to 180°C.

Activated lipidic cyclic carbonates for non-isocyanate polyurethane synthesis

Activated 5-membered cyclic carbonates were prepared from glycerol and fatty acid derivatives.

Thermoplastic polyester elastomers based on long-chain crystallizable aliphatic hard segments

Thermoplastic polyester elastomers prepared from a plant-oil derived crystallizable long-chain aliphatic α,ω-dicarboxylic acid have been investigated.

Hydrophobe-free miniemulsion polymerization: towards high solid content of fatty acid-based poly(urethane-urea) latexes

High solid content of aqueous fatty acid-based PU latexes.

ADMET polymerization of bio-based biphenyl compounds

Bio-based phenols were dimerized and employed as monomers in ADMET polymerization.

A high-molecular-weight and high-Tg poly(ester carbonate) partially based on isosorbide: synthesis and structure–property relationships

A new family of high-molecular-weight and high T_g poly(ester carbonate)s partially based on renewable isosorbide were prepared by incorporating 1,4-butanediol and dimethyl terephthalate into poly(isosorbide carbonate).

Polyols Prepared from Ring-Opening Epoxidized Soybean Oil by a Castor Oil-Based Fatty Diol

Several biorenewable vegetable oil-based polyols with different molecular weights and various hydroxyl functionalities were successfully prepared by ring-opening epoxidized soybean oil with a castor oil-based fatty diol. It was found that several factors, including reaction time, reaction temperature, and molar ratios between epoxidized soybean oil and castor oil diol, affect structures and rheology behaviors of the final polyols. Proton NMR, FT-IR, GPC, and rheometry results revealed that the hydroxyl functionalities, molecular weight, and viscosity of the polyols could be tailored by controlling the above-mentioned factors. Besides, the role of solvents in the epoxy ring-opening process was investigated as well.

Novel vanillic acid-based poly(ether–ester)s: from synthesis to properties

Two series of bio-based poly(ether–ester)s prepared from vanillic acid and linear α,ω-diols have been successfully synthesized by the direct esterification method. The mechanical properties of these poly(ether–ester)s are excellent, making them suitable materials for some practical applications.

Thermal and Kinetic Behaviour of Pongamia Glabra Oil Fatty Amide

N,N-bis(2-hydroxyl ethyl) Pongamia glabra oil fatty amide (HEPA) was synthesised by the aminolysis of pongamia oil. The structural elucidation of HEPA was carried out by FTIR, 1H NMR and 13C NMR spectroscopy. Physico-chemical studies were carried out by standard laboratory methods. Melting point of pongamia glabra oil and HEPA was measured through differential scanning calorimetry. Thermogravimetry/differential thermogravimetry analysis (TG/DTGA) was used to evaluate the thermal and kinetic behaviour of synthesised HEPA in nitrogen atmosphere under nonisothermal conditions with heating rates of 5, 10, 20, and 30 °C min−1. The TG curves of polymers at four heating rates were approximately in the same shape which indicated that mass loss is independent of heating rate. Obtained TGA data were analysed by the means of model-free isoconversional methods using Flynn–Wall–Ozawa and Kissinger–Akahira–Sunoseon applications on the whole range of temperature, and were found to be consistent. It was found that at the end of the decomposition process, the value of activation energy increases.

Facile and Highly Efficient Strategy for Synthesis of Functional Polyesters via Tetramethyl Guanidine Promoted Polyesterification at Room Temperature

A facile and highly efficient strategy for the synthesis of functional polyesters from 10-undecenoic acid, which is abundantly available and derived from ricin oil, has been successfully achieved using 1,1,3,3-tetramethyl guanidine (TMG) as a promoter at room temperature. The experimental results indicate that high molecular weight polyesters have been obtained and a variety of functional groups, such as alkenyl, alkynyl, nitro, epoxy, hydroxyl, and bromoisobutyrate, can be incorporated as pendant groups. The structures of the obtained polymers were demonstrated by ¹H and ¹³C NMR spectroscopy and their thermal properties were studied by DSC and TGA.