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Polyols are widely synthesized from fossil sources and applied in multiple sectors of the industry as raw material for polyurethane production and also as lubricants. Although the preparation method normally used is efficient and practical, it is necessary to develop environmentally friendly synthesis route that reduce pollution. This study focuses on an alternative synthetic route for the synthesis of polyols using only raw materials from renewable sources. Polyols were successfully obtained by modifying castor oil and epoxidized soybean oil through transesterification, transamidation and oxirane ring opening. The polyols were then characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H and 13C‐NMR), acidity index (AI), thermogravimetry (TGA), differential scanning calorimetry (DSC), size exclusion chromatography (SEC), dynamic viscosity and exploratory scanning of ecotoxicological parameters using Artemia salina. The results highlight the promising potential of transamidated castor oil (TACO) polyol in the field of biolubricants, attributed to its high viscosity index, oxidative stability and, ecofriendly behavior. [ABSTRACT FROM AUTHOR]

Vegetable oils are very promising alternatives to fossil lubricants due to their abundance, low cost, excellent performance, and environmental friendliness. Due to its multifunctional structure, castor oil is an excellent precursor in the synthesis of new biolubricants. However, it showed poor thermal‐oxidative stability and a higher pour point. This study used castor oil fatty acids prepared by transesterification (EHRO), epoxidation (TEPO), and oxirane ring opening with the aromatic amines aniline (ANIL) and p‐anisidine (ANIS). The chemical structure of these oils was verified by 1H and 13C NMR analysis, and mass spectrometry. Measurements show that the presence of an aromatic amine increases the viscosity resulting in 172 (ANIL) and 199 (ANIS) cSt at 40°C, but reduces viscosity index to 16 and 1, respectively. In addition, the amine groups can scavenge radicals increasing their thermal and oxidative stability. These products do not oxidize copper, and tribological analysis reveals that ANIS has the lowest torque with wear equivalent to commercial mineral lubricant NH‐140. [ABSTRACT FROM AUTHOR]

The alliance between 3D printing and nanomaterials brings versatile properties to pharmaceuticals, but few studies have explored this approach in the development of skin delivery formulations. In this study, clobetasol propionate (CP) was loaded (about 25% w/w) in mesoporous silica nanomaterial (MSN) to formulate novel bioadhesive and hydrophilic skin delivery films composed of pectin (5% w/v) and carboxymethylcellulose (5% w/v) by 3D printing. As a hydrophobic model drug, CP was encapsulated in MSN at a 3:1 (w/w) ratio, resulting in a decrease of CP crystallinity and an increase of its dissolution efficiency after 72 h (65.70 ± 6.52%) as compared to CP dispersion (40.79 ± 4.75%), explained by its partial change to an amorphous form. The CP-loaded MSN was incorporated in an innovative hydrophilic 3D-printable ink composed of carboxymethylcellulose and pectin (1:1, w/w), which showed high tensile strength (3.613 ± 0.38 N, a homogenous drug dose (0.48 ± 0.032 mg/g per film) and complete CP release after 10 h. Moreover, the presence of pectin in the ink increased the skin adhesion of the films (work of adhesion of 782 ± 105 mN·mm). Therefore, the alliance between MSN and the novel printable ink composed of carboxymethylcellulose and pectin represents a new platform for the production of 3D-printed bioadhesive films, opening a new era in the development of skin delivery systems. [ABSTRACT FROM AUTHOR]

Rigid polyurethane biofoams (RPUF) were produced by single shot-method using a bio-based polyol and 10 wt% of pinewood particles. Two different confinement degrees were investigated (70% and 50% of the free-rising volume), along with a control group produced under free-rising. RPUF were studied using SEM images (to estimate average foam cell size and anisotropy index), mechanical testing (under compression and tension), apparent density, and thermal conductivity analysis. The results were statistically evaluated using ANOVA tests prior to means tests. The RPUF produced under confinement showed more rounded and homogeneous cell structures compared to those freely expanded. The filled RPUF produced under a confinement degree of 50% yielded very high compressive and tensile strengths, whereas thermal conductivity decreased with confinement. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the influence of different water concentrations in the solvents of self-etching primers on microtensile bond strength (μTBS) of an experimental adhesive system. Materials and Methods: Five experimental self-etching primers with 0, 5, 10, 20 and 40 (wt%) water as solvent were formulated. An experimental adhesive resin (AD-50) was also synthesized to create one experimental self-etching adhesive system. Clearfil SE Bond (CSEB) was used as the commercial reference. Sixty bovine incisors were randomly separated into 6 groups. Buccal enamel was removed to expose the superficial coronal dentin; this surface was polished wet to create a standardized smear layer. After rinsing, water was removed, leaving the surface visibly dried. The dentin surfaces were etched with primer and air dried, adhesive resin was applied and photoactivated, then the composite resin restoration was placed. After storage for 24 h, the specimens were sectioned with a cooled diamond saw at low speed. Microtensile bond strength was measured and data were analyzed with one-way ANOVA/Tukey's test (α = 0.05). Results: ANOVA showed that primer composition was a significant factor for bond strength. There was no significant difference in bond strengths between the primers with a water concentration of 40% (53.9 ± 12.7 MPa), 20% (51.1 ± 11.5 MPa, and 10% (47.5 ± 11.4 MPa), and CSEB (50.7 ± 9.8 MPa). The groups with 5% (38.6 ± 12.9 MPa) and 0% (31.5 ± 7.5 MPa) water presented similar bond strengths amongst themselves but were statistically significantly lower than that of the other groups. Conclusion: The water concentration in the primer solvent exercises a significant influence on the bond strength of this experimental self-etching adhesive system. [ABSTRACT FROM AUTHOR]