Month: December 2022

Soars, Shafer published the artcileStimuli-Responsive Depolymerization of Poly(Phthalaldehyde) Copolymers and Networks, Safety of Pentaerythritol tetra(3-mercaptopropionate), the main research area is stimulus responsive depolymerization polyphthalaldehyde mercapto network.

This article describes a stimuli-responsive crosslinked network based on a poly(phthalaldehyde) (PPA) self-immolating polymer backbone which, upon removal of polymer end-caps, becomes degradable under ambient conditions. Self-immolating polymers (SIPs) are of particular interest due to their ability to undergo controlled depolymerization resulting in the elimination of the polymer structure and potential recovery and reuse of the original monomers. Linear copolymers of phthalaldehyde and unsym. allylated-phthalaldehyde monomers are obtained via anionic polymerization with appreciable incorporation of the allyl-functional monomeric units. This approach enables crosslinking of the otherwise linear polymers via thiol-ene reactions with the allyl functional phthalaldehyde polymers. The polymer network thus formed unzips along the phthalaldehyde backbone to yield monomers and low mol. weight fragments in response to chem. (F-, H+) or phys. (light, sonication) stimuli that remove the stabilizing functional endcaps on the phthalaldehyde polymers. Rheol. is used to demonstrate gelation within 5 s of light exposure of the allylated-phthalaldehyde polymers reacted with pentaerythritol tetrakis(3-mercaptopropionate) and photoinitiator (3 wt%). Triggerable degelation makes this material well suited for photolithog. and additive manufacturing as well as other applications that necessitate polymer network degradation or elimination. Further, a method is described for determining the degelation temperature of a self-immolative crosslinked network.

Macromolecular Chemistry and Physics published new progress about Crosslink density. 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

Lau, C. maggie published the artcileStructural Basis for the Different Mechanical Behaviors of Two Chemically Analogous, Carbohydrate-Derived Thermosets, COA of Formula: C17H28O8S4, the main research area is behavior analogous carbohydrate thermoset.

Two renewable, structurally analogous monomers, isosorbide undecenoate (IU) and glucarodilactone undecenoate (GDLU) reacted with pentaerythritol tetrakis(3-mercaptopropionate) (PETT) via thiol-ene photopolymerization to form IU-PETT and GDLU-PETT thermosets. Despite their chem. similarity, uniaxial tensile testing showed that GDLU-PETT exhibited a strain-hardening behavior and is significantly tougher than IU-PETT. To understand this observation, in situ tensile testing and wide- angle X-ray scattering experiments (WAXS) were conducted. While the 2D WAXS patterns of IU-PETT displayed an isotropic halo during uniaxial deformation, they exhibited a change from an isotropic halo to a pair of scattering arcs for the GDLU-PETT samples. D. functional theory calculations further revealed that the alkyl chains on GDLU adopt a linear conformation while the alkyl chains on IU are angled. Based on these results, we postulate that the linear GDLU mols. can more easily order and align during uniaxial deformation, hence increasing intermol. interactions between the GDLU mols. and contributing to the observed strain hardening behavior of their thermosets. This study exemplifies how mols. with subtle differences in their chem. structures can alter the structures and thermophys. properties of the resulting polymers in unpredictable ways.

ACS Macro Letters published new progress about Crosslink density. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, COA of Formula: C17H28O8S4.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Lu, Hai-Feng published the artcileUltrahigh fatigue resistant liquid crystal elastomer-based material enabled by liquid metal, Application In Synthesis of 7575-23-7, the main research area is acrylic liquid crystal elastomer fatigue resistance mech property.

The low crosslink d. characteristic of liquid crystal elastomer (LCE) materials causes poor fatigue resistance performance, which has seriously plagued their prospects in industrial applications. Here we report that the introduction of 5 wt% liquid metal nanodroplets (average diameter: ca. 195 nm) into the LCE network can dramatically reinforce the corresponding composite’s mech. properties, in particular ultrahigh fatigue resistance, capable of bearing unprecedented 10,000 tensile cycles within a large range of strain amplitude up to 70% and 2000 times of continuous actuating deformations. Furthermore, this liquid metal-incorporated LCE composite material exhibits large actuation stroke (maximum actuation strain: 55%), high actuation stress (blocking stress: 1.13 MPa), fully reversible thermal/photo-actuation functions, and self-healing ability at moderate temperatures, which qualifies the composite material for high-load actuators.

Science China Materials published new progress about Crosslink density. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Application In Synthesis of 7575-23-7.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Tian, Guangming published the artcileAn investigation on sunlight-induced shape memory behaviors of PCL/TiN composites film, Safety of Pentaerythritol tetra(3-mercaptopropionate), the main research area is polycaprolactone titanium nitride composite film shape memory behavior.

Plasmonic materials possess good optical properties in effectively converting solar energy into heat, here a series of sunlight responsive shape memory composites films based on acrylate-terminated Poly(ε-caprolactone) (PCL) and titanium nitride nanoparticles (TiN NPs) are prepared via base-catalyzed Michael addition Compared with conventional free radical polymerization or phys. blending, this paper constructs a network architecture from view of structural controllability, favoring a subsequent flexible and elastic materials as well as fine dispersion of TiN NPs in the crosslinked networks, the resultant materials show an outstanding mech. and the incorporated TiN NPs enable rapid temperature increase over the melting temperature of PCL and trigger the shape change of the composite with good shape recovery rate. The effect of light d. and TiN NPs concentration on composite film are elucidated and investigated systematically, it is found that the amount of TiN NPs content virtually has a negligible effect on the surface temperature of the films when subjected to a specific illumination, however, light intensity has a remarkable influence on it. Furthermore, an electronics device switch actuated by 160 mw cm-2 simulated sunlight irradiation is demonstrated and envisioned for flexible electronic applications.

Smart Materials and Structures published new progress about Crosslink density. 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

Luo, Chaoqian published the artcileReal-Time Alignment and Reorientation of Polymer Chains in Liquid Crystal Elastomers, Application In Synthesis of 7575-23-7, the main research area is real alignment reorientation polymer chain liquid crystal elastomer; Fourier-transform infrared spectroscopy; Mesogen alignment; liquid crystal elastomer; polarized optimal measurements; real-time characterization; reorientation.

Liquid crystal elastomers (LCEs) exhibit soft elasticity due to the alignment and reorientation of mesogens upon mech. loading, which provides addnl. mechanisms to absorb and dissipate energy. This enhanced response makes LCEs potentially transformative materials for biomedical devices, tissue replacements, and protective equipment. However, there is a critical knowledge gap in understanding the highly rate-dependent dissipative behaviors of LCEs due to the lack of real-time characterization techniques that probe the microscale network structure and link it to the mech. deformation of LCEs. In this work, we employ in situ optical measurements to evaluate the alignment and reorientation degree of mesogens in LCEs. The data are correlated to the quant. phys. anal. using polarized Fourier-transform IR spectroscopy. The time scale of mesogen alignment is determined at different strain levels and loading rates. The mesogen reorientation kinetics is characterized to establish its relationship with the macroscale tensile strain, and compared to theor. predictions. Overall, this work provides the first detailed study on the time-dependent evolution of mesogen alignment and reorientation in deformed LCEs. It also provides an effective and more accessible approach for other researchers to investigate the structural-property relationships of different types of polymers.

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

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Tratnik, Nicole published the artcileRecyclable, self-strengthening starch-based epoxy vitrimer facilitated by exchangeable disulfide bonds, Quality Control of 7575-23-7, the main research area is recycling starch epoxy vitrimer disulfide tensile crosslinking.

Epoxy vitrimers have emerged as a new class of self-healing, recyclable, and reprocessable materials, offering new opportunities to traditional epoxy thermosets by improving life-span, while providing addnl. functionalities. Nevertheless, retaining 100% of the original mech. performances remains difficult for vitrimers after several reprocessing cycles due to progressive changes in the vitrimer networks during rearrangements. In this study, we designed a novel epoxy vitrimer with a higher renewable content compared to conventional epoxies by using renewable materials. The bio-based epoxy vitrimer was synthesized from epoxidized starch amylopectin together with diallyl disulfide, that is naturally found in garlic, and a thiol (pentaerythritol tetrakis(3-mercaptopropionate) (PETMP)). Diallyl disulfide and PETMP enabled the formation of a recyclable, and reprocesseable, vitrimer network. The epoxy vitrimer displayed unprecedented self-strengthening after 5 recycling cycles (tensile strength increased over 900%) caused by the mech.-induced homogeneization of the diallyl disulfide/thiol and the starch epoxy ghost granule phases during the recycling process, thereby increasing the vitrimer crosslinking d. during reformation. Reprocessing the vitrimer 5-times improved the mech. and thermal properties, raising glass transition temperature, Young’s modulus, and tensile strength from 7°C to 25°C, 2.98 MPa to 268 MPa, and 1.87 MPa to 18.47 MPa, resp. Hence, capitalizing on mech.-induced phase homegeneization during the vitrimer reprocessing, this work introduces a strategy for the design of self-strengthening bio-based and recyclable thermosets.

Chemical Engineering Journal (Amsterdam, Netherlands) published new progress about Crosslink density. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Quality Control of 7575-23-7.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Ahangaran, Fatemeh published the artcileDevelopment of self-healing epoxy composites via incorporation of microencapsulated epoxy and mercaptan in poly(methyl methacrylate) shell, Category: alcohols-buliding-blocks, the main research area is epoxy mercaptan self healing agent PMMA microcapsule preparation property.

Self-healing composites based on epoxy resin containing poly(Me methacrylate) (PMMA) microcapsules filled with healing agents were prepared The effect of healing agents microcapsules on mech. properties and self-healing behavior of epoxy composites were investigated in this work. Epoxy and mercaptan as curing agent were microencapsulated in PMMA shell as two-component healing agent through internal phase separation method, and then, epoxy composites containing 2.5, 5, 7.5 and 10 wt% of healing agent microcapsules were prepared The fracture toughness and healing efficiency of these composites were measured using a tapered double cantilever beam (TDCB) specimen. The results indicated that about 80% healing efficiency was achieved with 10 wt% PMMA microcapsules at room temperature after 24 h. The tensile strength of the epoxy with 2.5 wt% PMMA microcapsules increased initially and then decreased gradually with increasing microcapsules content up to 10 wt% PMMA microcapsules. DSC results also indicated that this system has good potential for spontaneous self-healing performance at room temperature

Polymer Testing published new progress about Crack propagation. 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

Shen, Peng published the artcileHard-soft thiol-ene materials without interfacial weakness, Product Details of C17H28O8S4, the main research area is hard soft thiolene click material PDMS mold prepared property.

Thiol-ene materials are a series of materials that can be crosslinked using a suitable photo-initiator and a UV light source. An advantage of thiol-ene materials is that they can be tailored to have specific mech. properties by controlling the stoichiometry of the mixtures By combination of different reactants, it is therefore, in principle, possible to prepare monoliths with greatly varying mech. properties from essentially the same material. In this paper, we prepared an alternating hard and soft thiol-ene material with a sharp solid interface. Tetrakis (3-mercaptopropionate) (PETMP) with 1, 3, 5-triallyl-1, 3, 5-triazine-2, 4, 6(1H, 3H, 5 H)-trione (TATATO) as the hard segment exhibited strong tensile and compressive strength but had low elongation and weak bending stiffness. A mixture of PETMP and trimethylolpropane diallyl ether (TMPDE) was selected as the soft segment. After stretching at 0.001 s-1 using a filament stretching rheometer (FSR), the soft segment fractured at the strain of 21%, while the interface of the materials was strong enough to prevent cracking.

Materials Today Communications published new progress about Crack propagation. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Product Details of C17H28O8S4.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Laroussarie, Anais published the artcileSynthesis of the Tetrasaccharide Repeating Unit of the β-Kdo-Containing Exopolysaccharide from Burkholderia pseudomallei and B. cepacia Complex, Synthetic Route of 87905-98-4, the main research area is stereoselective glycosylation galactosylation coupling oligosaccharide KDO preparation exopolysaccharide Burkholderia.

The synthesis of the repeating unit of the immunogenic β-Kdo-containing exopolysaccharide produced by Burkholderia pseudomallei and bacteria of the B. cepacia complex is described. The target tetrasaccharide was synthesized via stereoselective 1,2-cis- and 1,2-trans-galactosylation and β-Kdo formation. A [3+1] coupling reaction between a trigalactosyl N-phenyl-2,2,2-trifluoroacetimidate donor and a Kdo acceptor has been successfully achieved for the assembly of the tetrasaccharide skeleton.

Journal of Organic Chemistry published new progress about Coupling reaction. 87905-98-4 belongs to class alcohols-buliding-blocks, name is Benzyl (5-hydroxypentyl)carbamate, and the molecular formula is C13H19NO3, Synthetic Route of 87905-98-4.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Ramirez-Contreras, Rodrigo published the artcileChemo- and Regioselective Functionalization of Polyols through Catalytic C(sp3)-C(sp3) Kumada-Type Coupling of Cyclic Sulfate Esters, Synthetic Route of 58783-82-7, the main research area is chemoselective regioselective functionalization Kumada type coupling cyclic sulfate ester; copper catalyst coupling cyclic sulfate ester alkyl Grignard reagent.

This contribution describes a copper-catalyzed, C(sp3)-C(sp3) cross-coupling reaction of cyclic sulfate esters, a distinct class of electrophilic derivatives of polyols, with alkyl Grignard reagents to afford functionalized alc. products in good yields. The method is operationally simple and highlights the potential of cyclic sulfate esters as highly reactive substrates in catalytic, chemoselective polyol transformations.

Organic Letters published new progress about Coupling reaction. 58783-82-7 belongs to class alcohols-buliding-blocks, name is 5-Tridecanol, and the molecular formula is C13H28O, Synthetic Route of 58783-82-7.

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts