Tag: M.W=400-500

Correr-Sobrinho, Lourenco published the artcileStrengthening ceramic surfaces with the use of resin cements based on thiourethane oligomers, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate), the main research area is strengthening ceramic surface resin cement thiourethane oligomer.

This study evaluated the effects of thiourethane (TU) additives on the flexural strength (σf) and elastic modulus (Ef) of a resin cement, and on a possible strengthening of ceramic restorations. Methods : Two TUs (Aromatic and Aliphatic) were added at 0 (control-EC) or 20 wt% to photopolymerizable resin cements. RelyX Ultimate (RU) was the com. control. Flexural strength (σf) and elastic modulus (Ef) of the cements were measured in three-point bending (n = 8). Biaxial flexural strength (σbf) of ceramic disks with and without cement layering were determined using a ball-on-ring setup. The σbf of cement-coated specimens was calculated at positions z = 0 (ceramic surface, bonded interface) and z = -t2 (cement surface above ring). Data were analyzed with one-way ANOVA/Tukey test (α = .05). Results : σf of AR was significantly higher than for AL and RU, and Ef was lower. The Ef of RU was significantly higher than all other groups. At z = 0, all resin-coated groups had higher σbf. The σbf of RU, AR, and AL were significantly higher than EC and unfilled resin group. At z = -t2, RU had significantly higher σbf. Significance : All resin cements were able to strengthen the ceramic, with the TU-modified material presenting similar results to the com. material.

Journal of Applied Polymer Science published new progress about Adhesives. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate).

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Li, Yi published the artcileReconfigurable Three-Dimensional Mesotructures of Spatially Programmed Liquid Crystal Elastomers and Their Ferromagnetic Composites, Safety of Pentaerythritol tetra(3-mercaptopropionate), the main research area is reconfigurable mesotructure programmed liquid crystal elastomer ferromagnetic composite.

Reversible programming of 3D soft mesostructures is desired for many applications including soft robotics and biomedical devices. The large, reversible shape changes of liquid crystal elastomers (LCEs), which result from the coupling between the alignment of liquid crystal (LC) mols. and the macroscopic deformation of polymer networks, have attracted much attention for such applications. Here, a facile and versatile strategy is introduced to create reconfigurable, freestanding 3D mesostructures of LCEs and magnetic LCE composites that are inaccessible with existing techniques via spatially programming LC mols. through mech. buckling. Demonstrations include exptl. and theor. results of more than 20 reconfigurable 3D LCE mesostructures of diverse configurations, from coils and spirals to structures that resemble fences and frameworks, with characteristic feature sizes and thicknesses ranging from micro to macro. The large, reversible shape-switching behaviors of these structures over multiple cycles are also demonstrated. An LCE gripper is shown to grab/release objects of both regular and irregular geometries. Furthermore, a robot of ferromagnetic LCE composites that simultaneously responds to magnetic and thermal stimuli for diverse biomimetic behaviors, especially crawling underneath a narrow crack, illustrates the integration of other functional materials to LCEs for multifunctional systems.

Advanced Functional Materials published new progress about Adhesives. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Safety of Pentaerythritol tetra(3-mercaptopropionate).

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Martinez, Alina M. published the artcileTunable Surfaces and Films from Thioester Containing Microparticles, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate), the main research area is tunable surface film thioester microparticle.

Reported here, thioester containing microparticles were designed with 40% excess thiol to enable thiol-thioester exchange to facilitate the formation of cohesive films from the particles. A thiol-Michael dispersion polymerization was used to generate thioester containing microparticles with a diameter of 4.0 ± 0.4μm. The particles were then swollen with a base at varying concentrations to activate the thiol-thioester exchange and subsequently compressed between two glass slides. Resultant films were characterized over time with profilometry and at. force microscopy (AFM) to infer particle coalescence at different catalyst loadings and times. Tensile tests were performed confirming the structural integrity of the particle-based films. Furthermore, microparticles were welded to a nondynamic network demonstrating feasibility in potential applications to generate materials containing differing mech. properties. Being able to control the functionality of particles, and thus mech. properties of the resultant films, is also important for applications in coatings, adhesives, and 3D printing where spatial patterning or selective material property control is needed.

ACS Applied Materials & Interfaces published new progress about Adhesives. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate).

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Han, Di published the artcileEngineering the Surface Pattern of Microparticles: From Raspberry-like to Golf Ball-like, Synthetic Route of 7575-23-7, the main research area is microparticle surface structure shape silsesquioxane; golf ball-like; microparticles; polyhedral oligomeric silsesquioxane; raspberry-like; thiol−epoxy polymerization.

Control of the shape and uniformity of colloid particles is essential for realizing their functionality in various applications. Herein, we report a facile approach for the synthesis of narrowly dispersed anisotropic microparticles with well-defined raspberry-like and golf ball-like surface patterns. First, we demonstrate that hybrid raspberry-like particles can be achieved through a one-pot polymerization method using glycidyl polyhedral oligomeric silsesquioxane (GPOSS) and pentaerythritol tetra(3-mercaptopropionate) (PETMP) as monomers. Varying the polymerization parameters such as catalyst loading, monomer concentration, and the molar ratio of monomers, we are able to regulate the sizes and surface protrusion numbers of these raspberry-like microparticles. The formation mechanism is attributed to a competition balance between thiol-epoxy reaction and thiol-thiol coupling reaction. The former promotes rapid formation of large core particles between PETMP and GPOSS droplets (which can serve as core particles), while the latter allows for generation of surface protrusions by PETMP self-polymerization, leading to the formation of raspberry-like surface patterns. Based on the different POSS contents in the surface protrusions and cores of the raspberry-like microparticles, we demonstrate that they can be used as precursors to produce microporous silica (sub)microparticles with golf ball-like morphol. via pyrolysis subsequently. Overall, this work provides a facile yet controllable approach to synthesize narrowly dispersed anisotropic microparticles with diverse surface patterns.

ACS Applied Materials & Interfaces published new progress about IR spectra. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Synthetic Route of 7575-23-7.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Uda, Ryoko M. published the artcileMalachite green leuco derivatives as photobase generators for initiating crosslinking and polymerization, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate), the main research area is malachite green derivative photobase generator crosslinking anionic photopolymerization initiator.

We investigated the pH-changing profile induced by UV irradiation of malachite green leuco derivatives (MG-Xs) and performed polymerization and crosslinking reactions initiated by irradiated MG-Xs. A substituent (X) is covalently linked to the central carbon atom of malachite green, abbreviated as MG-OH or MG-OCH3. MG-Xs undergo photoionization to afford malachite green cations and anions (X-), which act as photobase generators. We found that MG-OCH3 was as effective as MG-OH for photoionization and photo-induced pH jumping. Anionic photo-polymerization of Me methacrylate was accomplished via irradiation of MG-Xs. Irradiation of MG-Xs triggered the base-promoted crosslinking reaction between pentaerythritol tetra(3-mercaptopropionate) and hexamethylene diisocyanate.

Materials Letters published new progress about Leuco dyes. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate).

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Zhang, Mingchao published the artcileLiquid-Crystal-Elastomer-Actuated Reconfigurable Microscale Kirigami Metastructures, Category: alcohols-buliding-blocks, the main research area is liquid crystal elastomer polyester polyether polythioester microscale kirigami metastructure; kirigami; liquid crystal elastomers; reconfigurable metastructures; two-photon polymerization; wireless microscale devices.

Programmable actuation of metastructures with predesigned geometrical configurations has recently drawn significant attention in many applications, such as smart structures, medical devices, soft robotics, prosthetics, and wearable devices. Despite remarkable progress in this field, achieving wireless miniaturized reconfigurable metastructures remains a challenge due to the difficult nature of the fabrication and actuation processes at the micrometer scale. Herein, microscale thermo-responsive reconfigurable metasurfaces using stimuli-responsive liquid crystal elastomers (LCEs) is fabricated as an artificial muscle for reconfiguring the 2D microscale kirigami structures. Such structures are fabricated via two-photon polymerization with sub-micrometer precision. Through rationally designed experiments guided by simulations, the optimal formulation of the LCE artificial muscle is explored and the relationship between shape transformation behaviors and geometrical parameters of the kirigami structures is build. As a proof of concept demonstration, the constructs for temperature-dependent switching and information encryption is applied. Such reconfigurable kirigami metastructures have significant potential for boosting the fundamental small-scale metastructure research and the design and fabrication of wireless functional devices, wearables, and soft robots at the microscale as well.

Advanced Materials (Weinheim, Germany) published new progress about Actuators. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Category: alcohols-buliding-blocks.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Wang, Meng published the artcileLiquid crystal elastomer actuator with serpentine locomotion, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate), the main research area is liquid crystal elastomer actuator serpentine locomotion.

A snake-mimic soft actuator composed of a bilayered liquid crystal elastomer ribbon and two serrated feet is reported in this work. Under repeated on/off near-IR light irradiation, this actuator can move forward relying on a reversible shape morphing between S-curve structure and reverse S-curve structure, which is similar to the serpentine locomotion of snakes.

Chemical Communications (Cambridge, United Kingdom) published new progress about Actuators. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Recommanded Product: Pentaerythritol tetra(3-mercaptopropionate).

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Sheima, Yauhen published the artcileTransient Elastomers with High Dielectric Permittivity for Actuators, Sensors, and Beyond, Computed Properties of 7575-23-7, the main research area is elastomer dielec permittivity actuator sensor; dielectric constant; high dielectric permittivity elastomers; low-voltage actuation; transient actuators; transient dielectrics; transient electronics; transient sensors.

Dielec. elastomers (DEs) are key materials in actuators, sensors, energy harvesters, and stretchable electronics. These devices find applications in important emerging fields such as personalized medicine, renewable energy, and soft robotics. However, even after years of research, it is still a great challenge to achieve DEs with increased dielec. permittivity and fast recovery of initial shape when subjected to mech. and elec. stress. Addnl., high dielec. permittivity elastomers that show reliable performance but disintegrate under normal environmental conditions are not known. Here, we show that polysiloxanes modified with amide groups give elastomers with a dielec. permittivity of 21, which is 7 times higher than regular silicone rubber, a strain at break that can reach 150%, and a mech. loss factor tan δ below 0.05 at low frequencies. Actuators constructed from these elastomers respond to a low elec. field of 6.2 V μm-1, giving reliable lateral actuation of 4% for more than 30 000 cycles at 5 Hz. One survived 450 000 cycles at 10 Hz and 3.6 V μm-1. The best actuator shows 10% lateral strain at 7.5 V μm-1. Capacitive sensors offer a more than a 6-fold increase in sensitivity compared to standard silicone elastomers. The disintegrated material can be re-crosslinked when heated to elevated temperatures In the future, our material could be used as dielec. in transient actuators, sensors, security devices, and disposable electronic patches for health monitoring.

ACS Applied Materials & Interfaces published new progress about Actuators. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Computed Properties of 7575-23-7.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Javed, Mahjabeen published the artcileProgrammable Shape Change in Semicrystalline Liquid Crystal Elastomers, Computed Properties of 7575-23-7, the main research area is programmable shape change semicrystalline liquid crystal elastomer; actuator; crystallization; liquid crystal elastomers; polymers; stimuli-responsive.

Liquid crystal elastomers (LCEs) are stimuli-responsive materials capable of reversible and programmable shape change in response to an environmental stimulus. Despite the highly responsive nature of these materials, the modest elastic modulus and blocking stress exhibited by these actuating materials can be limiting in some engineering applications. Here, we engineer a semicrystalline LCE, where the incorporation of semicrystallinity in a lightly cross-linked liquid crystalline network yields tough and highly responsive materials. Directed self-assembly can be employed to program director profiles through the thickness of the semicrystalline LCE. In short, we use the alignment of a liquid crystal monomer phase to pattern the anisotropy of a semicrystalline polymer network. Both the semicrystalline-liquid crystalline and liquid crystalline-isotropic phase transition temperatures provide controllable shape transformations. A planarly aligned sample’s normalized dimension parallel to the nematic director decreases from 1 at room temperature to 0.42 at 250°. The introduction of the semicrystalline nature also enhances the mech. properties exhibited by the semicrystalline LCE. Semicrystalline LCEs have a storage modulus of 390 MPa at room temperature, and monodomain samples are capable of generating a contractile stress of 2.7 MPa on heating from 25 to 50°, far below the nematic to isotropic transition temperature The robust mech. properties of this material combined with the high actuation strain can be leveraged for applications such as soft robotics and actuators capable of doing significant work.

ACS Applied Materials & Interfaces published new progress about Actuators. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Computed Properties of 7575-23-7.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Liu, Haoran published the artcileAn electrically actuated soft artificial muscle based on a high-performance flexible electrothermal film and liquid-crystal elastomer, Computed Properties of 7575-23-7, the main research area is elec actuator soft artificial muscle flexible electrothermal film elastomer; flexible electrothermal film; high heating rate; high saturation temperature; soft artificial muscle; stable resistance.

Liquid-crystal elastomer (LCE)-based soft robots and devices via an electrothermal effect under a low driving voltage have attracted a great deal of attention for their ability on generating larger stress, reversible deformation, and versatile actuation modes. However, electrothermal materials integrated with LCE easily induce the uncertainty of a soft actuator due to the non-uniformity on temperature distribution, inconstant resistance in the deformation process, and slow responsivity after voltage on/off. In this paper, a low-voltage-actuated soft artificial muscle based on LCE and a flexible electrothermal film is presented. At 6.5 V, a saturation temperature of 189°C can be reached with a heating rate of 21°C/s, which allows the soft artificial muscle quick and significant contraction and is suitable for untethered operation. Meanwhile, uniform temperature distribution and stable resistance of the flexible electrothermal film in the deformation process are obtained, leading to a work d. of 9.97 kJ/m3, an actuating stress of 0.46 MPa, and controllable deformation of the soft artificial muscle. Finally, programmable low-voltage-controlled soft artificial muscles are fabricated by tailoring the flexible electrothermal film or designing structured heating pattern, including a prototype of soft finger-like gripper for transporting small objects, which clearly demonstrates the potential of low-voltage-actuated soft artificial muscles in soft robotics applications.

ACS Applied Materials & Interfaces published new progress about Actuators. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Computed Properties of 7575-23-7.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts