Browse
Submit Data
Databases
API
Help

Dataset Information

31 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Preparation and Properties of Low Dielectric Constant Siloxane/Carbosilane Hybrid Benzocyclobutene Resin Composites.

ABSTRACT: Benzocyclobutene-modified silsesquioxane (BCB-POSS) and divinyl tetramethyl disiloxane-bisbenzocyclobutene (DVS-BCB) prepolymer were introduced into the containing benzocyclobutene (BCB) unit matrix resin P(4-MB-co-1-MP) polymerized from 1-methyl-1-(4-benzocyclobutenyl) silacyclobutane (4-MSCBBCB) and 1-methyl-1-phenylsilacyclobutane (1-MPSCB), respectively. The low dielectric constant (low-k) siloxane/carbosilane hybrid benzocyclobutene resin composites, P(4-MB-co-1-MP)/BCB-POSS and P(4-MB-co-1-MP)/DVS-BCB, were prepared. The curing processes of the composites were assessed via Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The effects on dielectric properties and heat resistance of those composites with different proportion of BCB-POSS and DVS-BCB were investigated using an impedance analyzer and thermogravimetric analyzer (TGA), respectively. The thermal curing of composites could be carried out by ring-opening polymerization (ROP) of the BCB four-member rings of BCB-POSS or DVS-BCB and those of P(4-MB-co-1-MP). With increasing the proportion of BCB-POSS to 30%, the 5% weight loss temperature (T_5%) of P(4-MB-co-1-MP)/BCB-POSS composites was raised visibly, whereas the dielectric constant (k) was decreased owing to the introduction of nanopores into POSS. For P(4-MB-co-1-MP)/DVS-BCB composites, the T_5% and k were slightly raised with increasing the proportion of DVS-BCB. The above results indicated that the BCB-POSS showed advantages over conventional fillers to simultaneously improve thermostability and decrease k.

SUBMITTER: Li X

PROVIDER: S-EPMC8585461 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Preparation of UV-Curable Low Surface Energy Polyurethane Acrylate/Fluorinated Siloxane Resin Hybrid Coating with Enhanced Surface and Abrasion Resistance Properties.

Project description:Low surface energy coatings have gained considerable attention due to their superior surface hydrophobic properties. However, their abrasion resistance and sustainability of surface hydrophobicity are still not very satisfactory and need to be improved. In this work, a series of utraviolet (UV)-curable fluorosiloxane copolymers were synthesized and used as reactive additives to prepare polyurethane acrylate coatings with low surface energy. The effect of the addition of the fluorinated graft copolymers on the mechanical durability and surface hydrophobicity of the UV-cured hybrid films during the friction-annealing treatment cycles was investigated. The results show that introducing fluorosiloxane additives can greatly enhance surface hydrophobicity of the hybrid film. With addition of 2 wt.% fluorosiloxane copolymers, the water contact angle (WCA) value of the hybrid film was almost tripled compared to that of the pristine PU film, increasing from 58° to 144°. The hybrid film also showed enhanced abrasion resistance and could withstand up to about 60 times of friction under a pressure of 20 kPa. The microstructure formed in the annealed film was found to contribute much to achieve better surface hydrophobicity. The polyurethane acrylate/fluorinated siloxane resin hybrid film prepared in this study exhibits excellent potential for applications in the low surface energy field.

| S-EPMC7143720 | biostudies-literature

Synthesis of Carbosilane and Carbosilane-Siloxane Dendrons Based on Limonene.

Project description:In this work, carbosilane dendrons of the first, second, and third generations were obtained on the basis of a natural terpenoid, limonene. Previously, we have shown the possibility of selective hydrosilylation and hydrothiolation of limonene. It is proved that during hydrosilylation, only the isoprenyl double bond reacts, while the cyclohexene double bond does not undergo into the hydrosilylation reaction. However, the cyclohexene double bond reacts by hydrothiolation. This selectivity makes it possible to use limonene as a dendron growth center, while maintaining a useful function-a double bond at the focal point. Thus, the sequence of hydrosilylation and Grignard reactions based on limonene formed carbosilane dendrons. After that, the end groups were blocked by heptamethyltrisiloxane or butyllithium. The obtained substances were characterized using NMR spectroscopy, elemental analysis and GPC. Thus, the proposed methodology for the synthesis of carbosilane dendrons based on the natural terpenoid limonene opens up wide possibilities for obtaining various macromolecules: dendrimers, Janus dendrimers, dendronized polymers, and macroinitiators.

| S-EPMC9416742 | biostudies-literature

Dielectric Properties of Hybrid Polyethylene Composites Containing Cobalt Nanoparticles and Carbon Nanotubes.

Project description:Polymer composites with electrically conductive inclusions are intensively developed for microwave shielding applications, where lightweight and elastic coatings are necessary. In this paper, dielectric properties of hybrid polyethylene composites containing cobalt nanoparticles and multi-wall carbon nanotubes (MWCNT) were investigated in the wide frequency range of 20-40 GHz for electromagnetic shielding applications. The percolation threshold in the hybrid system is close to 6.95 wt% MWCNT and 0.56 Co wt%. Cobalt nanoparticles (up to highest investigated concentration 4.8 wt%) had no impact on the percolation threshold, and for the fixed total concentration of fillers, the complex dielectric permittivity is higher for composites with bigger MWCNT concentrations. Moreover, the microwave complex dielectric permittivity of composites with high concentration of fillers is quite high (for composites with 13.4 wt% MWCNT and 1.1 wt% Co ε' ≈ ε″ ≈ 20 at 30 GHz, it corresponds to microwave absorption 50% of 1 mm thickness plate); therefore, these composites are suitable for electromagnetic shielding applications.

| S-EPMC8912063 | biostudies-literature

Hybrid Polycarbosilane-Siloxane Dendrimers: Synthesis and Properties.

Project description:A series of carbosilane dendrimers of the 4th, 6th, and 7th generations with a terminal trimethylsilylsiloxane layer was synthesized. Theoretical models of these dendrimers were developed, and equilibrium dendrimer conformations obtained via molecular dynamics simulations were in a good agreement with experimental small-angle X-ray scattering (SAXS) data demonstrating molecule monodispersity and an almost spherical shape. It was confirmed that the glass transition temperature is independent of the dendrimer generation, but is greatly affected by the chemical nature of the dendrimer terminal groups. A sharp increase in the zero-shear viscosity of dendrimer melts was found between the 5th and the 7th dendrimer generations, which was qualitatively identical to that previously reported for polycarbosilane dendrimers with butyl terminal groups. The viscoelastic properties of high-generation dendrimers seem to follow some general trends with an increase in the generation number, which are determined by the regular branching structure of dendrimers.

| S-EPMC7922192 | biostudies-literature

Hydrocarbon Resin-Based Composites with Low Thermal Expansion Coefficient and Dielectric Loss for High-Frequency Copper Clad Laminates.

Project description:The rapid development of the 5G communication technology requires the improvement of the thermal stability and dielectric performance of high-frequency copper clad laminates (CCL). A cyclic olefin copolymer (COC) resin was added to the original 1,2-polybutadienes (PB)/styrene ethylene butylene styrene (SEBS) binary resin system to construct a PB/SEBS/COC ternary polyolefin system with optimized dielectric properties, mechanical properties, and water absorption. Glass fiber cloths (GFCs) and SiO2 were used to fill the resin matrix so to reduce the thermal expansion coefficient (CTE) and enhance the mechanical strength of the composites. It was found that the CTE of polyolefin/GFCs/SiO2 composite laminates decreased with the increase of SiO2 loading at first, which was attributed to the strong interfacial interaction restricting the segmental motion of polymer chains between filler and matrix. It was obvious that the addition of COC and SiO2 had an effect on the porosity, as shown in the SEM graph, which influenced the dielectric loss (Df) of the composites directly. When the weight of SiO2 accounted for 40% of the total mass of the composites, the laminates exhibited the best comprehensive performance. Their CTE and Df were reduced by 63.3% and 22.0%, respectively, and their bending strength increased by 2136.1% compared with that of the substrates without COC and SiO2. These substrates have a great application prospect in the field of hydrocarbon resin-based CCL.

| S-EPMC9182675 | biostudies-literature

Comparison of the Properties of Epoxy Resins Containing Various Trifluoromethyl Groups with Low Dielectric Constant.

Project description:A series of epoxy resins containing various trifluoromethyl groups were synthesized and thermally cured with diaminodiphenylmethane (DDM) and aminophenyl sulfone (DDS). All epoxy resins exhibited excellent thermal stability with the glass transition temperatures of above 128 °C and 5% weight loss temperatures of above 300 °C. DDS-cured epoxy resins possessed higher thermal stability than that of DDM-cured epoxy resins, while DDM-cured epoxy resins showed better mechanical, dielectric, and hydrophobic properties. Additionally, DDM-cured epoxy resins with different locations and numbers of trifluoromethyl groups showed flexural strength in the range of 95.55~152.36 MPa, flexural modulus in the range of 1.71~2.65 GPa, dielectric constant in the range of 2.55~3.05, and water absorption in the range of 0.49~0.95%. These results indicate that the incorporation of trifluoromethyl pendant groups into epoxy resins can be a valid strategy to improve the dielectric and hydrophobic performance.

| S-EPMC10346801 | biostudies-literature

Enhancing the mechanical properties and providing bioactive potential for graphene oxide/montmorillonite hybrid dental resin composites.

Project description:This in vitro study synthetized hybrid composite nanoparticles of graphene oxide (GO) and montmorillonite MMt (GO-MMt) by ultrasound treatments. Samples were characterized by X-ray diffraction, FT-Raman, FTIR, TEM and SEM. The effect of their incorporation (0.3% and 0.5%) on the mechanical properties in a resin-based composite (RBC) and their bioactivity potential were evaluated. The specimens were characterized by evaluating their 3-point flexural strength (n = 6), modulus of elasticity (n = 6), degree of conversion (n = 6), microhardness (n = 6), contact angle (n = 3) and SEM analysis (n = 3). In vitro test in SBF were conducted in the RBCs modified by the hybrid. Overall, the synthetized hybrid composite demonstrated that GO was intercalated with MMt, showing a more stable compound. ANOVA and Tukey test showed that RBC + 0.3% GO-MMt demonstrated superior values of flexural strength, followed by RBC + 0.5% GO-MMt (p < 0.05) and both materials showed higher values of microhardness. All groups presented a contact angle below 90°, characterizing hydrophilic materials. RBCs modified by the hybrid showed Ca and P deposition after 14 days in SBF. In conclusion, RBCs composed by the hybrid showed promising results in terms of mechanical properties and bioactive potential, extending the application of GO in dental materials.

| S-EPMC9205868 | biostudies-literature

Dielectric Relaxation in the Hybrid Epoxy/MWCNT/MnFe2O4 Composites.

Project description:The electrical properties of epoxy/MWCNT (multi-walled carbon nanotubes)/MnFe2O4 hybrid composites loaded with MWCNTs (below, 0.09 vol.%, and above, 0.58 vol.%, percolation threshold) and varying concentrations of MnFe2O4 up to 10 vol.% were studied in a wide frequency range (20 Hz-40 GHz) at different temperatures (20 K-500 K). At low frequencies, the dielectric permittivity and the electrical conductivity of composites with fixed amounts of MWCNT are strongly dependent on MnFe2O4 content. For MWCNT concentrations above the percolation threshold (i.e., 0.58 vol.%), the electrical conductivity highly decreases with the increase of the MnFe2O4 fraction. In contrast, for the epoxy/MWCNT just below the onset of electrical conductivity (0.09 vol.% of MWCNTs), there exists an optimal concentration of MnFe2O4 inclusions (i.e., 0.025 vol.%), leading to a dramatic increase of the electrical conductivity by three orders of magnitude. The electrical transport in composites is mainly governed by electron tunneling at lower temperatures (below 200 K), and it is highly impacted by the matrix conductivity at higher temperatures (above 400 K). The electrical properties were discussed in terms of the Maxwell-Wagner relaxation and distributions of relaxation times. A non-invasive platform based on dielectric relaxation spectroscopy was proposed for enhancing the synergetic effect coursed by using multiple nanoinclusions in polymer composites just below the percolation threshold.

| S-EPMC7183270 | biostudies-literature

Low Dielectric Constant Photocurable Fluorinated Poly (Phthalazinone Ether) Ink with Excellent Mechanical Properties and Heat Resistance.

Project description:The photosensitive resins for 3D printing technology have been widely applied throughout the advanced communication field due to their merits of high molding accuracy and fast processing speed. Regardless, they, in particular, should have better mechanical properties, heat resistance, and dielectric properties. Herein, photocurable fluorinated poly (phthalazinone ether) (FSt-FPPE) was utilized as a prepolymer to improve the performance of photosensitive resin. A series of UV-curable inks named FST/DPGs were prepared with FSt-FPPE and acrylic diluents of different mass fractions. The FST/DPGs were cured into films by UV curing and post-treatment. After curing, their properties were characterized in detail. In terms of heat resistance, glass transition temperature (Tg) could reach 233 °C and the 5% thermal decomposition temperature (Td5%) was 371 °C. The tensile strength surprisingly reached 61.5 MPa, and the dielectric constant (Dk) could be significantly reduced to 2.75. Additionally, FST/DPGs were successfully employed in UV-assisted direct writing (DIW) to print 3D objects that benefited from their commendable fluidity and rapid curing speed. A stiff cylinder sample with a smooth surface and distinct pattern was ultimately obtained, indicating their remarkable 3D printing adaptation. Such photosensitive resin for UV-assisted DIW exhibits tremendous potential in the electronic industry.

| S-EPMC10051853 | biostudies-literature

Cytocompatible and Antibacterial Properties of Chitosan-Siloxane Hybrid Spheres.

Project description:Microporous spheres in a hybrid system consisting of chitosan and ?-glycidoxypropyltrimethoxysilane (GPTMS) have advantages in a range of applications, e.g., as vehicles for cell transplantation and soft tissue defect filling materials, because of their excellent cytocompatibility with various cells. In this study, microporous chitosan-GPTMS spheres were prepared by dropping chitosan-GPTMS precursor sols, with or without a cerium chloride, into liquid nitrogen using a syringe pump. The droplets were then freeze dried to give the pores of size 10 to 50 ?m. The cell culture tests showed that L929 fibroblast-like cells migrated into the micropores larger than 50 ?m in diameter, whereas MG63 osteoblast-like cells proliferated well and covered the granule surfaces. The spheres with cerium chloride showed antibacterial properties against both gram-negative and gram-positive bacteria.

| S-EPMC6835879 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data