Thermal Stable Polymer Research Articles

Femtosecond laser-induced ultrafast growth of volcanic-shaped graphene micropillars

Surface micropillars are capable of significantly altering material properties, including anti-reflection, structural color, wettability, and adhesion. Conventional methods for fabricating micropillars are both time-intensive and material-consuming. Recently, a nature-inspired light-induced self-growth method has been proposed to avoid the drawbacks of conventional methods. However, this method suffers from slow growth rates (slower than 3.3 × 102 μm/s) and restricted precursor material (limited to heat-shrinkable shape-memory polymer). Herein, we developed the light-induced method based on femtosecond laser thermal accumulation engineering and realized the self-growth of micropillars on thermal-stable polymers. By inducing localized carbonization rather than heat shrinkage with a high repetition rate laser, given the instantaneous release of large amounts of gases and highly localized stresses during laser carbonization, unique graphene micropillars grow rapidly and spontaneously from the polyimide surface with a growth rate of 4.5 × 103 μm/s. The growth rate of micropillars is increased by an order of magnitude compared to previously reported light-induced methods. Furthermore, the dimensions of these micropillars, including height, diameter, and spacing, can be precisely controlled by modulating the heat accumulation. Last but not least, solar absorbers and light-driven actuators are flexibly fabricated using this method, demonstrating its practical applicability.

Graphene skeletal nanotemplate coordinated with pH-Responsive porous Double-Ligand Metal-Organic frameworks (DL-MOFs) through ligand exchange theory for High-Performance smart coatings

For the first time, thermally stable and high-performance pH-responsive anti-corrosive nanoreservoirs based on double-ligand zinc phosphate framework (ZPF) decorated graphene oxide skeletal template (G-ZPF) was prepared through the ligand exchange theory. The G-ZPF nanoreservoirs, and pristine materials were monitored by X-ray diffraction (XRD), Thermo gravimetric analysis (TGA), Field emission scanning electron microscopy (FE-SEM), Fourier transforms infrared (FT-IR) spectroscopy, and Brunauer-Emmett-Teller (BET) analyses. The outcomes revealed that a highly thermal stable double-ligand porous coordination polymer was synthesized properly. pH-responsive corrosion inhibitors release ability of G-ZPF nanoreservoirs was studied in the acidic, neutral, and alkaline saline (3.5 wt% concentration of NaCl) solutions, and the release rate of active corrosion inhibiting substances (Zinc and phosphate ions, and 2-methylimidazole molecules) was measured by inductively coupled plasma-optical emission spectrometry (ICP-OES), and total organic carbon (TOC) techniques. Electrochemical (polarization, and EIS), and surface analyses were conducted for investigating the G-ZPF nanoreservoirs corrosion inhibition ability in the saline solution, and mild steel samples coated with the epoxy-polyamide incorporated with G-ZPF nanoreservoirs in intact and scratched forms. The results showed that structural inhibitors-loaded G-ZPF nanoreservoirs guarantee both active (self-healing), and passive (ion- water barrier) characteristics of the organic coating. The results of Pull off, salt spray, cathodic disbonding, dynamic mechanical analysis (DMTA), and tensile tests showed robust corrosion prevention and excellent thermo/mechanical performance of the epoxy-polyamide coating loaded with G-ZPF nanoreservoirs.

Improved Mechanical, Anti-UV Irradiation, and Imparted Luminescence Properties of Cyanate Ester Resin/Unzipped Multiwalled Carbon Nanotubes/Europium Nanocomposites

Cyanate ester resin (CER) is an excellent thermal stable polymer. However, its mechanical properties are not appropriate for its application, with brittle weakness, and it has poor functional properties, such as luminescence. This work innovatively combines the luminescence property and the improved mechanical properties with the inherent thermal property of cyanate ester. A novel nanocomposite, CER/uMWCNTs/Eu, with multi-functional properties, has been prepared. The results show that with the addition of 0.1 wt.% of uMWCNTs to the resin, the flexural strength and tensile strength increased 59.3% and 49.3%, respectively. As the curing process of the CER progresses, the injected luminescence signal becomes luminescence behind the visible (FBV). The luminescence intensity of CER/uMWCNTs/Eu was much stronger than that of CER/MWCNTs/Eu, and the luminescence lifetime of CER/MWCNTs/Eu and CER/uMWCNTs/Eu was 8.61 μs and 186.39 μs, respectively. FBV exhibited great potential in the embedment of photon quantum information. Therefore, it can be predicted that CER/uMWCNTs/Eu composites will not only have a wide range of applications in sensing, detection, and other aspects, but will also exhibit great potential in the embedding of photon quantum information.

A thermal and pH stable fluorescent coordination polymer for sensing nitro explosives or metal ions with high selectivity and sensitivity in aqueous solution

A new zinc(II) coordination polymer (Zn-CP) constructed from 4,4-dipyridyldiphenyl ether (BPDPE) and 1,2-benzenedicarboxylic acid (1,2-bdc), namely [Zn2(1,2-bdc)2(BPDPE)2]n (1), has been discovered using the solvothermal method. Complex 1 is a two-dimensional sheet with uncoordinated pyridine group composed of one-dimensional chain [Zn(1,2-bdc)]n connected by BPDPE, and finally forms a three-dimensional network through π···π interactions. Complex 1 shows excellent thermo and acid/base stability in aqueous solutions with a pH of 2–12. Further research indicates that complex 1 has high selectivity for the detection of TNP and Fe3+ by fluorescence sensing. The quenching constant (Ksv) is 1.99 × 104 M for TNP with the detection limit (LOD) of 2.54 × 10−6 M; the Ksv is 1.0 × 104 M for Fe3+, and LOD is 6.1 × 10−6 M. In addition, the mechanisms of fluorescence quenching have been studied experimentally and theoretically.

Direct Preparation of High Thermal Stable PLA‐Based Nanocomposite via Extra‐Low Loading of In Situ Exfoliated Ultrathin MWW Zeolite Nanosheets

AbstractPoly(lactic acid) (PLA)‐based nanocomposite incorporated with zeolite MCM‐22 precursor at extra‐low loading of 0.2–0.8 wt% is directly prepared by melt compounding and injection moulding method. The Vicat softening temperature raises up to >155 °C, much higher than that of pure PLA (63 °C), which is very beneficial for its application in many fields such as a container for hot food due to its environmentally friendly property. The high heat resistance property is believed to not be caused by the improvement of crystallinity and glass transition temperature but resulting from the obstruction of PLA polymer chain movement originating from >CO···HOSi hydrogen bonding between PLA molecules and the in situ exfoliated MWW zeolite nanosheets with abundant exposed surface silanol groups. Such a method would pave a new way not only for designing more types of thermal stable polymer composites but also for delaminating multi‐layered zeolite precursors.

Schiff Base polymers: synthesis and characterization

The reaction between a carbonyl group (aldehyde or ketone) with amine in suitable condition, the Schiff base compounds with an amine group with the general structure R1R2C=NR3 (R3 ≠ H) was prepared [1, 2]. These compounds were first prepared by German scientist Hugo Schiff. The Schiff base compounds are widely used as a ligand in the coordination chemistry [3, 4]. The division of these compounds is diverse and depending on the various parameters, they are divided into symmetric, asymmetrical, anionic, neutral types and etc. But in most cases the division of these compounds is based on the number of atoms that are coordinated to the center ion. Accordingly, they are divided into mono-, bi- and multi-dentate ligands. Important groups of these compounds are chelated bi-and tetra-dentate ligands, which can be obtained from the reaction of salicylic aldehyde and amine derivatives [5, 6]. The simplicity of providing, having different colors, stabilizing metal complexes and diverse applications has led many research groups to work on these compounds [1, 2, 5, 6]. The most important properties of these compounds are anion sensor [6–8] and avoid steel corrosion [9, 10]. In recent years the innovation of novel Schiff base polymers as thermally stable polymers play a vital role in many areas, among that the most important factor of thermally stable polymers for different industry. Because of that, these advances are interested in improvement of heat and thermal stability and safety. Day to day in this globalization, thermal stable polymers requires a long shelf life, along with monitoring the safety and quality based upon international standards. In this chapter it inculcates, thermally stable polymers such as PA, PI and PES and its stability, long life, mechanical and thermal properties for different applications.

Highly effective synthesis of dimethyl carbonate over CuNi alloy nanoparticles @Porous organic polymers composite

Greenhouse effect raised by the carbon dioxide emissions has become a pivotal resolved issue at present. The direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol is one of infusive green pathways. In this study, a novel CuNi alloy nanoparticles encapsulated in a thermal stable triphenylphosphine porous organic polymers (POP-PPh3), CuxNiy@POP-PPh3 catalysts, is synthesized and then explored in the direct DMC synthesis reactions. The CuxNiy@POP-PPh3 catalysts are fully characterized by a series of techniques, such as transmission electron microscopy (TEM) with energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), N2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy (XPS), and hydrogen temperature programmed reduction (H2-TPR). TEM images show the CuNi particles are around 7 nm, and XPS analyses demonstrate the alloy particles comprise of a metallic (CuNi)0 core and a thin Ni2O3 surface. The CuxNiy@POP-PPh3 catalysts, fixed into a honeycomb ceramic to give a monolithic catalyst, show an excellent catalytic performance (a 10.5% methanol conversion with an 80% DMC selectivity) during the direct DMC synthesis reactions in a fixed bed reactor. The high catalytic performance over CuxNiy@POP-PPh3 catalysts is mainly attributed to the pore structure of POP-PPh3, uniform distribution of alloy nanoparticles, and the unique performance of the monolithic catalyst (e.g., removing by-product of water in time).

Conversion of Langmuir–Blodgett monolayers and bilayers of poly(amic acid) through polyimide to graphene

Various solid carbon sources, particularly poly(methyl methacrylate), have been used as precursors to graphene. The corresponding growth process generally involves the decomposition of the solids to hydrocarbon gases followed by their adsorption on metallic substrates (e.g., Cu). We report a different approach that uses a thermally-resistant polyimide (PI) as a carbon precursor. Langmuir–Blodgett films of poly(amic acid) (PAA) were transferred to copper foils and then converted to graphene via a PI intermediate. The Cu foil substrate was also discovered to facilitate the orientation of aromatic moieties upon carbonization process of the PI. As approximately 50% of the initial quantity of the PAA was found to remain at 1000 °C, thermally-stable polymers may reduce the quantity of starting material required to prepare high quality films of graphene. Graphene grown using this method featured a relatively large domain size and an absence of adventitious adlayers.

Biomass trans-anethole-based heat-resistant copolymer microspheres: Preparation and thermostability

Preparing biobased heat-resistant vinyl polymers remains as a big challenge. We successfully used trans-anethole (ANE), a typical natural and sustainable vinyl compound with abundant sources yet scarcely taken for preparing polymers, for preparing polymer microspheres through copolymerizing it with N-phenylmaleimide (N-PMI). The copolymer microspheres were efficiently obtained with high yield (>87%), clean surface, good spherical morphology, and narrow size distribution (CV=6.22%) by free radical precipitation polymerization. The content of ANE units in the copolymer was found to be approximately 50mol%. Growth of the microspheres was investigated in detail. Glass transition temperature (Tg) and decomposition temperature of the present copolymers were up to respectively 170 and 380°C, which cannot be achieved in normal polymeric microspheres. The present biobased microspheres are expected to find practical applications as novel thermal stable polymer materials and heat-resistant additives.

Preparation of some thermal stable polymers based on diesters of polyethylene and polypropylene oxides macro monomers to use as surfactants at high temperature and pressure

Based on polyethylene (PE) and polypropylene (PP) oxides, six macromonomers were prepared through two steps. The first step was esterification of the PE and PP oxides, with oleic acid to give the corresponding monoesters. The second was the diesterfication of the prepared monoesters with methacrylic acid to give the corresponding diesters. The prepared macromonomers (diesters) were polymerized to obtain six polymers. The chemical structure of the prepared mono- and diesters and polymers was justified by IR, NMR, GPC and TGA. The obtained results confirmed that the prepared polymers have a high thermal stability and can be used in high pressure and temperature during the drainage of the water from water-in-oil emulsions. The surface active and thermodynamics parameters of these polymers in non-aqueous solution were also investigated and it was found that, these materials have high thermal stability which leads to the possibility to be used under severe reservoir conditions as surfactants.

Novel propargylether‐terminated monomers containing pyridine and phenyl pendent group: Synthesis, cure, and properties

ABSTRACTTwo novel propargylether‐terminated resins containing pyridine and bulky phenyl pendent group were prepared from propargyl bromide and different diphenols, and highly thermal stable polymers were obtained by the thermal cure of the monomers. The chemical structures of these novel monomers were well confirmed by FTIR, 1H‐NMR and elemental analysis. Curing and thermal behavior of the resins were investigated using differential scanning calorimetry (DSC) and dynamic thermogravimetry in argon atmosphere. DSC curves of these two monomers showed a single endothermic peak corresponding to the conformation of chromene ring and homopolymerization of the chromene ring. The temperature at 5% weight loss (Td5) was higher than 440°C under argon and the highest glass transition temperature (Tg) reached 362°C. The rheological behavior and solubility of the monomer were also investigated. The monomers showed excellent flow‐ability, broad processing window, and great solubility. These results showed that the two resins could be ideal candidates for high‐temperature resistant resins. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40469.

Polyelectrolyte based on tetra-sulfonated poly(arylene ether)s for direct methanol fuel cell

A series of tetra-sulfonated poly(arylene ether)s are prepared from a new tetra-sulfonated difluoride monomer and commercial 4,4′-difluorobenzophenone and 4,4′-(hexafluoroisopropylidene)diphenol via polycondensation process. With the content of tetra-sulfonated monomer raising from 15% to 35% in difluoride monomer, sulfonated polymers with ion exchange capacity (IEC) ranging from 0.92 to 1.66 mequiv g−1 are obtained. The high thermal stable polymer owns the glass transition temperature higher than 190 °C and onset decomposition temperature higher than 300 °C. The polymers exhibit good solubility in dimethylacetamide (DMAc) and the tough, flexible and transparent films are obtained by solution casting method. These membranes exhibit suitable proton conductivity, low methanol permeability and excellent dimensional stability. The membrane with IECE = 1.81 mequiv g−1 shows considerable proton conductivity (84 mS cm−1) and swelling ration (only 8.6%) under fully hydrated state at 100 °C. Their excellent performance is attributed to distinct phase separation between hydrophilic and hydrophobic morphology, which is observed by TEM. This work demonstrates that the strategy of combining locally high densities hydrophilic segment with fluorine-containing hydrophobic segment in a polymer chain can balance on proton conduction and dimensional stability efficiently. Furthermore, these membranes own much lower methanol permeability and higher selectivity than Nafion.

Synthesis and Characterization of a Novel Linear Benzoxazine-Containing Polytriazole via Metal-Free Click Reaction and its Self-Crosslinking Behavior

A novel linear benzoxazine-containing polytriazole was successfully synthesized via metal-free click reaction. Benefited from the advantages of click reaction, the synthesis procedure was easily and efficiently. The linear polymer could be transformed into crosslinked structure after ring-opening polymerization of oxazine induced by the increasing temperature. The FT-IR characterization verified the structure transformation between linear and crosslinked polymer. Moreover, the thermal properties and thermal degradation behaviors of linear polymer and the corresponding crosslinked polymer were studied by DSC and TGA. The novel polytriazole was proved to be a kind of thermal stable polymers with high thermal decomposition temperature (Td5over 300°C).

Recent progress in negative-working photosensitive and thermally stable polymers

The production of semiconductors, especially for semiconductor large-scale integration (LSI), has been definitely supported by photolithographic technologies using photosensitive polymers in the micro-electronic device industry. Among them, photosensitive and thermally-stable polymers (PSTSPs) provide simpler resist system than the conventional one, in which the resist materials stays after forming a pattern and function as thermally resisting insulators in integrated circuits (ICs) and multi-chip packages (MCPs), eliminating the extra process of resist removal. Recently, negative-working chemical amplification photoresists have started to receive much attention as quite simple and direct network formation systems in polymer films. The recent progress in negative-working PSTSPs based on the chemical amplification system is summarized in this review article, which includes low dielectric constant polymers for LSI, high refractive index polymers for microlens materials in complementary metal oxide semiconductor image sensors, novolac resists for indium tin oxide patterning, and poly(3-hexylthiophene) for organic field-effect transistors.

The novel [(dME)2(HIM)P]2Ti(IV) complex: synthesize, characterization, and its utility in ROP of d,l-lactide

The novel {2,4-bis(1,1-dimethylethyl)-6-{[(2-hydroxyethyl)imino]methyl}phenoxy}2 titanium(IV) complex {[(dME)2(HIM)P]2Ti(IV)} had been synthesized and characterized by EA, XRF, IR, and NMR methods. The [(dME)2(HIM)P]2Ti(IV) complex was reactive and promoted ring-opening polymerization (ROP) of d,l-lactide in the presence of benzyl alcohol (BnOH). And the results showed that ROP of d,l-lactide were produced upon addition of an excess (1–8 equiv.) of external BnOH. The complex showed a living and controlled fashion (M w/M n = 1.15–1.32) for ROP of d,l-lactide and could produce the poly(d,l-lactide) with average molecular weight (M n) up to 8.87 × 104 g mol−1. The mechanism study by 1H NMR spectrum of poly(d,l-lactide) with terminal benzyl ester group and [(dME)2(HIM)P]2Ti(IV) complex revealed that the polymerization proceeded through the traditional activated monomer mechanism and the acyl-oxygen bond cleavage mode of monomer. And the 13C NMR spectra and TG/DSC analysis showed that poly(d,l-lactide) was essential atactic and thermal stable polymer.

Stabilization of poly(3-hexylthiophene)/PCBM morphology by hydroxyl group end-functionalized P3HT and its application to polymer solar cells

A new concept to stabilize the morphology of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C 61-butyric acid methyl ester (PCBM) blend through H-bond formation by using a hydroxyl group end-functionalized P3HT (HOC-P3HT-COH) as a compatibilizer is presented. Domain size of the PCBM crystals in the annealed P3HT/PCBM film is diminished with addition of HOC-P3HT-COH. Surface roughness of the P3HT/PCBM film also becomes smoother with addition of HOC-P3HT-COH. Thermal stability of solar cell device is improved significantly through the H-bond formation between HOC-P3HT-COH and PCBM. A high performance and thermal stable polymer solar cell with 4.06% power conversion efficiency under AM1.5G irradiation is fabricated with 5% HOC-P3HT-COH in P3HT/PCBM layer.

Synthesis of N-cyanoalkyl-functionalized imidazolium nitrate and dicyanamide ionic liquids with a comparison of their thermal properties for energetic applications

The synthesis of 10 N-alkyl-N-cyanoalkyl-functionalized imidazolium (N-methyl- and N-butyl-N-((CH2)nCN)imidazolium; n = 1–4) nitrate and 11 N-alkyl-N-cyanoalkyl-functionalized imidazolium (N-methyl-N-((CH2)nCN)imidazolium; n = 1–6, N-(2-cyanoethyl)-N-((CH2)nCN)imidazolium; n = 1,3–6) dicyanamide salts was achieved via N-alkylation of substituted imidazoles with commercially available haloalkylnitriles followed by anion exchange. Based on their observed melting points, all dicyanamide salts and all but one nitrate salt (1-cyanomethyl-3-methylimidazolium nitrate) had melting points <100 °C, as did 13 of the 17 halide precursors also reported here. Differential scanning calorimetry data indicated that melting points decreased by increasing the N-alkyl or N-cyanoalkyl chain length or by exchanging with the dicyanamide anion, which produced the lowest melting points in comparison to analogous halide or nitrate salts. Thermogravimetric analyses indicated that thermal stability increased for longer N-cyanoalkyl substituent lengths and decreased significantly for nitrates and more so for dicyanamides bearing short-chain N-cyanoalkyl substituents (e.g., N-cyanomethyl, N-(1-cyanoethyl), and N-(2-cyanoethyl)) in comparison to halide precursors. Furthermore, for many of the N-cyanoalkyl-substituted salts (especially the dicyanamides), there was a significant production of thermally-stable char – presumably due to by-products formed from the reaction of either N-cyanoalkyl substituents, dicyanamide anion, or both, which resulted in thermally-stable polymers or cycles.

Synthesis and properties of sulfonated aromatic fluoro‐polymers

AbstractPolycondensation of perfluorobiphenyl with α,α‐bis(4‐hydroxyphenyl)ethylbenzene and/or 9,9‐bis(4‐hydroxyphenyl)fluorene was investigated. The polycondensation of perfluorobiphenyl with α,α‐bis(4‐hydroxyphenyl)ethylbenzene and/or 9,9‐bis(4‐hydroxyphenyl)fluorene proceeded at low‐temperature to a give high‐molecular weight and thermal stable polymers. The 19F‐NMR spectra of the polymers indicate that the polymers consists of predominantly 1,4‐phenylene structure with respect to the perfluoro‐aromatic compound. The sulfonation of the polymers obtained from the polycondensation occurred at the phenyl groups and fluorenyl side chain. A tough and smooth film was prepared by a casting method from DMF solution of the sulfonated polymer. The films showed hydrolytic and oxidative stabilities, and a high‐proton conductivity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Fabrication of Carbonyl Iron Embedded Polycarbonate Composite Particles and Magnetorheological Characterization

Carbonyl iron (CI)-based magnetorheological (MR) fluid exhibits serious dispersion defect due to large density mismatch between CI particles and continuous medium, which obviously restricts further MR application. Thus, various modifications on CI particles have been explored, among which embedding CI particles within polymer matrix attracted much attention because the density of fabricated polymer/CI particles got considerably low, consequently enhancing the dispersion stability. In this paper, a more thermal stable polymer, polycarbonate (PC) with high strength, toughness, and heat resistance was adopted as polymer matrix, in which CI particles were randomly embedded via a facile solvent casting method. The embedding structure and density were confirmed by SEM/OM images and pycnometer, respectively. Finally, MR characterization was investigated.

Syntheses and properties of cross‐linked polymers from functionalized triglycerides

AbstractA number of functionalized triglycerides were synthesized from glyceryl trioleoate via epoxidation followed by reduction to give glyceryl tris(9‐hydroxy)trioleoate (a triol) or hydrolytic ring opening to obtain glyceryl tris(9,10‐dihydroxy)trioleoate (a hexaol). A selective monoepoxidation reaction of glyceryl trioleoate was also carried out and the resulting monoepoxide was hydrolyzed to give glyceryl 9,10‐dihydroxytrioleoate (a diol). Glyceryl tris(9‐hydroxy)trioleoate was brominated followed by displacement with sodium azide and reduction to give glyceryl tris(9‐amino)trioleoate (a triamine) and glyceryl tris[9‐(N‐isopropylamino)]trioleoate. These functionalized triglycerides were crosslinked with 1,4‐phenylene diisocyanate. The crosslinked polymers exhibit thermoset characteristics. Thermal analysis results suggest that the polymers are in amorphous states, and their thermal stability was significantly affected by crosslink degree. The crosslinked polymer derived from the diol retained 56% of its weight at 408°C, whereas the polymers derived from the aforementioned hexaol with higher crosslink degree retained only 36% of the original weight. Glass transition temperatures of these polymers range from −1.0°C to 10.2°C. The thermal stable polymer, 12, derived from the aforementioned diol exhibits a linear viscoelastic character and can be used as thermoplastics. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008