Properties of composite solid polymer electrolyte using hyperbranched polymer with ether-linkage

The cross-linked composite solid polymer electrolytes composed of poly(ethylene oxide), lithium salt (LiN(SO₂CF₃)₂), and a hyperbranched polymer whose repeating units were connected by ether-linkage (hyperbranched polymer (HBP)-2) were prepared, and their ionic conductivity, thermal properties, electrochemical stability, mechanical property, and chemical stability were investigated in comparison with the non-cross-linked or cross-linked composite solid polymer electrolytes using hyperbranched polymers whose repeating units were connected by ester-linkage (HBP-1a, 1b). The cross-linked composite solid polymer electrolyte using HBP-2 exhibited higher ionic conductivity than the non-cross-linked and cross-linked composite solid polymer electrolytes using HBP-1a and HBP-1b, respectively. The structure of the hyperbranched polymer did not have a significant effect on the thermal properties and electrochemical stability of the composite solid polymer electrolytes. The tensile strength of the cross-linked composite solid polymer electrolyte using HBP-2 was lower than that of the cross-linked composite solid polymer electrolyte using HBP-1b, but higher than that of the non-cross-linked composite solid polymer electrolyte using HBP-1a. The HBP-2 with ether-linkage showed higher chemical stability against alkaline hydrolysis compared with HBP-1a with ester-linkage.     

Elaboration of corona functionalized regular unimolecular hyperbranched polystyrene nanoparticles

Functional arborescent graft polystyrenes prepared by the “graft-on-graft” technique, involving the iterative grafting of end functional polymer chains onto reactive polymer backbones were synthesized. The zero-generation comb polymers and then the first generation hyperbranched structures were obtained by the coupling reaction of living α-acetal polystyryllithium onto linear or comb chains of poly(chloroethyl vinyl ether) (PCEVE) of controlled D̄P̄_n and structure. Both the PS grafts and the PCEVE reactive backbones were synthesized individually by living polymerization techniques. Initiation of styrene polymerization from acetal functionalized lithium derivatives yield the ω-functionalization of all external polystyrene branches. Derivatization of these acetal branch termini allowed the generation of aldehyde, hydroxyl and carboxyl groups as well as the introduction of functional organic molecules at the periphery of the nanoparticles.     

Synthesis of multi-arm star polystyrene with hyperbranched polyether core

Multi-arm star polystyrenes with hyperbranched poly(3-ethyl-3-oxetanemethanol) (PEOM, 3) core were synthesized by atom transfer radical polymerization (ATRP) method. The structures of polymers were confirmed by FT-IR and ¹H NMR. GPC results showed that the resultant polymers had relatively low polydispersity indices (PD = 1.47-2.03). DSC analysis indicated that polystyrene star polymers had a glass transition temperature (T_g = 42.2-91.5 °C) that changed with the amount of the polystyrene in the polymers. In addition, the aggregation behavior of the multi-arm star polystyrenes in a selective solvent (THF/cyclohexane) was probed with polystyrene arms that encapsulated in the aggregates and PEOM cores hidden in the center of the micelles.     

可控降解超支化聚碳硅氮烷的合成与表征

通过锂化四甲基二乙烯基二硅氮烷分别与甲基氢二氯硅烷和二甲基氢氯硅烷的亲核取代反应合成了AB4和AB2型单体AB4M和AB2M,两种单体通过Karstedt催化剂催化的硅氢加成反应分别生成聚碳硅氮烷PAB4M和PAB2M.单体和聚合物的结构通过FT-IR、1H-NMR、13C-NMR、29Si-NMR和体积排除色谱-多角度激光光散射联用(SEC-MALLS)技术进行了表征,结果表明,单体的结构与设计结构相符合;单体聚合时主要以α-硅氢加成方式为主;聚合物具有超支化结构并由N(Si—C)3链节和大量端基双键组成.PAB4M和PAB2M的重均分子量分别为7800和5860g/mol,分子量分布系数分别为2·54和2·31·对PAB4M稳定性的初步研究表明,该聚合物对氯硅烷和在中性条件下对水稳定,但在HCl水溶液中可以降解,且通过控制HCl浓度可以调节其降解速度,从而实现对其控制降解.     

Synthesis and characterization of novel hyperbranched poly(imide silsesquioxane) membranes

A new family of hyperbranched polymers with chemical bonds between the hyperbranched polyimide and polysilsesquioxane network was synthesized by the reaction of an amine‐terminated aromatic hyperbranched polyimide with 3‐glycidoxypropyl trimethoxysilane, followed by hydrolysis and polycondensation in the presence of an acid catalyst. The hyperbranched poly(imide silsesquioxane) membranes were fabricated by the casting the aforementioned polymer solution onto a NaCl optical flat, which was followed by heating at 80 °C for 24 h. The membranes were characterized by Fourier transform infrared, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy, N₂ adsorption and desorption, and CO₂ adsorption and desorption. The presence of covalent bonds between the hyperbranched polyimide and polysilsesquioxane segments had a significant effect on the properties of the membranes. N₂ adsorption–desorption isotherms for these membranes showed surface areas of 6–16 m²/g, whereas CO₂ adsorption–desorption isotherms showed much higher surface areas in the range of 106–127 m²/g. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3736–3743, 2003     

Second-order nonlinear optical hyperbranched polymers via facile ring-opening addition reaction of azetidine-2,4-dione

A new hyperbranched polymeric structure was chosen as a nonlinear optical material. First, a difunctional chromophore, 4-(4′-nitrophenyl-diazenyl) phenyl-1,3-diamine (NDPD) was synthesized, which was then reacted with 4-isocyanato-4′(3,3-dimethyl-2,4-dioxo-azetidino)diphenylmethane (MIA) to form NDPDMIA (A₂ type monomer). The azetidin-2,4-dione functional groups exhibit selective reactivity, which can react only with primary amines under mild conditions. The hyperbranched polymers were synthesized via ring-opening addition reaction between azetidine-2,4-dione (A₂ type monomer) and primary amine (B₃ type monomer). This synthetic scheme comes with easy purification, high yield and rapid synthesis. Chemical structures of the hyperbranched polymers were characterized by FT-IR, ¹H NMR, and elemental analysis. The inherent viscosity of hyperbranched polymers in DMSO ranged from 0.15 to 0.22 dLg⁻¹. All of the obtained polymers were soluble in DMF, DMAc, and DMSO. Using in situ contact poling, r₃₃ coefficients of 6-16 pm/V and their temporal stability at 60 °C were obtained. Optical loss measurement was also achieved by a prism coupling setup.     

Synthesis of novel low-viscosity liquid epoxidized aromatic hyperbranched polymers

Low-viscosity liquid epoxidized aromatic hyperbranched polymers are synthesized by the reaction between epichlorohydrin (ECH) and carboxy-end hyperbranched polymers prepared from low-cost products trimellitic anhydride (B₃ TMA) and dihydroxy alcohols (A₂). The low-viscosity property, especially the lowest viscosity of epoxidized aromatic hyperbranched polymers is only 350 cp which has not reported among epoxidized aromatic hyperbranched polymers before, make them can be used to coatings and adhesion fields without organic solvent hopefully. The properties of the epoxidized aromatic hyperbranched polymers are measured by GPC, FT-IR and viscometer.     

Synthesis and characterization of dendronized hyperbranched polymers through the “A<Subscript>3</Subscript>+B<Subscript>2</Subscript>” approach

Dendronized hyperbranched polymer (DHP) is a new kind of polymer, which combines the advantages of dendrimers and hyperbranched polymers. In this work, two dendronized hyperbranched polymers, DHPG0 and DHPG1, were successfully prepared through the simple “A₃+B₂” type Sonogashira coupling reaction. The nonlinear optical (NLO) effects of DHPG0 and DHPG1, characterized by the d ₃₃ values, were 183 and 220 pm V^–1 respectively, higher than those of their analogues of dendronized polymers and dendrimers, thanks to the special topological structure. Also, the obtained polymers displayed excellent solubility, good processability, and high thermal stability.     

Effects of hyperbranched and linear architecture on properties of polymers composed of poly(ɛ-caprolactone) and hydroxycinnamic acid

Photoreactive and degradable polymers with linear and hyperbranched architectures which composed of poly(?-caprolactone) and hydroxycinnamic acid or its substituted derivatives were synthesized by thermal melt-polycondensation. The chemical structures of the polymers were confirmed by FTIR and ¹H NMR measurements. The polymers showed good photoreactivities and fluorescent properties, and the hyperbranched polymers showed higher photoreactive speed and weaker fluorescence properties. These polymers had excellent thermal stabilities due to the rigid conjugated structures and the π-π strcking interaction of the cinnamoyl group, especially for the hyperbranched polymer. Moreover, the hydrolysis experiments and the XRD results revealed that the hyperbranched and linear polymers are amorphous and crystalline, respectively, and the degradation rate of amorphous polymers are faster than crystalline samples.     

One‐pot synthesis and characterization of hyperbranched poly(ester‐amide)s from commercially available dicarboxylic acids and multihydroxyl secondary amines

A convenient and cost‐effective strategy for synthesis of hyperbranched poly(ester‐amide)s from commercially available dicarboxylic acids (A₂) and multihydroxyl secondary amine (CB₂) has been developed. By optimizing the conditions of model reactions, the AB₂‐type intermediates were formed dominantly during the initial reaction stage. Without any purification, the AB₂ intermediate was subjected to thermal polycondensation in the absence of any catalyst to prepare the aliphatic and semiaromatic hyperbranched poly(ester‐amide)s bearing multi‐hydroxyl end‐groups. The FTIR and ¹H NMR spectra indicated that the polymerization proceeded in the proposed way. The DBs of the resulting polymers were confirmed by a combination of inverse‐gated decoupling ¹³C NMR, and DEPT‐135 NMR techniques. The DBs of the hyperbranched poly(ester‐amide)s were in the range of 0.44–0.73, depending on the structure of the monomers used. The hyperbranched polymers exhibited moderate molecular weights with relatively broad distributions determined by SEC. All the polymers displayed low inherent viscosity (0.11–0.25 dL/g) due to the branched nature. Structural and end‐group effects on the thermal properties of the hyperbranched polymers were investigated using DSC. The thermogravimetric analysis revealed that the resulting polymers exhibit reasonable thermal stability. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5077–5092, 2008     

Synthesis and characterization of N‐substituted hyperbranched polyureas

N,N′‐disubstituted hyperbranched polyureas with methyl, benzyl, and allyl substitutents were synthesized starting from AB₂ monomers based on 3,5‐diamino benzoic acid. Carbonyl azide approach, which generates isocyanate group in situ on thermal decomposition, was used for the protection of isocyanate functional groups. The N‐substituted hyperbranched polymers can be considered as the new class of internally functionalized hyperbranched polyureas wherein the substituent can function either as receptor or as a chemical entity for selective transformations as a tool to tailor the properties. The chain‐ends were also modified by attaching long chain aliphatic groups to fully realize the interior functionalization. This approach opens up a possible synthetic route wherein different functional substituents can be used to generate a library of internally functionalized hyperbranched polymers. All the hyperbranched polyureas were characterized by FTIR, ¹H‐NMR, DSC, TGA, and size exclusion chromatography. Degree of branching in these N,N′‐disubstituted hyperbranched polyureas, as calculated by ¹H‐NMR spectroscopy using model compounds, was found to be lower than the unsubstituted hyperbranched polyurea and is attributed to the lower reactivity of N‐substituted amines compared to that of unsubstituted amines. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5134–5145, 2004     

Convenient Synthesis and Enhanced Second-order Nonlinear Optical Property of a Novel Hyperbranched Polymer

A novel hyperbranched polymer （3） was prepared by copolymerization of tri-aldehyde moieties with azo chromophores having two active methelene groups, from ＂A2＋B3＂ approach based on simple Kneovenagel reaction. For comparison, its analogue linear polymer （5） was also synthesized. The two polymers are soluble in common organic solvents, and exhibit good thermal stability. Interestingly, the hyperbranched polymer demonstrates dramatically enhanced second-order nonlinear optical property with comparison to its linear analogue.     

Michael addition polymerizations of difunctional amines (AA′) and triacrylamides (B3)

Novel hyperbranched poly(amido amine)s containing tertiary amines on the backbones and acryl or secondary amines as the surface groups were successfully synthesized via the Michael addition polymerizations of a triacrylamide [1,3,5‐triacryloylhexahydro‐1,3,5‐triazine (TT)] and a difunctional amine [n‐butylamine (BA)] NMR techniques were used to clarify the structures of hyperbranched polymers and polymerization mechanism. The reactivity of the secondary amine formed in situ was much lower than that of the primary amines in BA. When the feed molar ratio was 1:1 TT/BA, the secondary amine formed in situ was almost kept out of the reaction before the BA (AA′) and TT (B₃) monomers were consumed, and this led to the formation of A′B₂ intermediates containing one secondary amine group and two acryl groups. The self‐polymerization of the A′B₂ intermediates produced hyperbranched polymers bearing acryl as surface groups. For the polymerization with the feed molar ratio of 1:2 TT/BA, A′₂B intermediates containing one acryl group and two secondary amine groups were accumulated until self‐polymerization started; the self‐polymerization of the intermediates formed hyperbranched polymers with secondary amines as their surface groups. Modifications of surface functional groups were studied to form new hyperbranched polymers. The hyperbranched poly(amido amine)s were amorphous. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6226–6242, 2006     

Synthesis of hyperbranched polymers with precise conjugation length

A set of AB₂ type monodisperse conjugated oligomers carrying two bromo functional groups and one boronic ester functional group were prepared by iterative deprotection and Sonogashira cross‐coupling reactions. Suzuki polycondensation of these AB₂ type monodisperse oligomers afforded hyperbranched polymers. The hyperbranched conjugated polymers we prepared possess not only precisely controlled conjugation length like monodisperse conjugated oligomers but also the structural feature of hyperbranched polymers. Optical property investigation demonstrated that the maximum absorption and emission wavelength red‐shifted along with the increasing of the conjugation length between the two branching points and the hyperbranched structure could effectively reduce the aggregation of the conjugated polymer chains. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1084–1092, 2007     

Novel Functional Conjugative Hyperbranched Polymers with Aggregation‐Induced Emission: Synthesis Through One‐Pot “A2+B4” Polymerization and Application as Explosive Chemsensors and PLEDs

With the aim to develop new tetraphenylethylene (TPE)‐based conjugated hyperbranched polymer, TPE units, one famous aggregation‐induced emission (AIE) active group, are utilized to construct hyperbranched polymers with three other aromatic blocks, through an “A₂+B₄” approach by using one‐pot Suzuki polycondensation reaction. These three hyperbranched polymers exhibit interesting AIEE behavior and act as explosive chemsensors with high sensitivity both in the nanoparticles and solid states. This is the first report of the AIE activity of the TPE‐based conjugated hyperbranched polymers. Their corresponding PLED devices also demonstrate good performance.     

Surface-relief-grating formation behavior of two hyperbranched azo polymers

In this work,surface-relief-grating formation behavior was studied by using two hyperbranched azo polymers.The hyperbranched polymers containing pseudo-stilbene type azo chromophores throughout the hyperbranched structure were synthesized by step-growth polycondensation of AB₂ type monomers.The AB₂ monomer,4-（4’-（bis（2-chloroethyl）amino）-phenylazo） benzoic acid（BAA）,was prepared through azo-coupling reaction between N,N’-bis（2-chloroethyl）aniline and 4- aminobenzenic acid.The another AB₂ monomer,4-（4’-（bis（2-chloroethyl）amino）phenylazo）-3-nitro-benzoic acid（BANA）, was prepared through azo-coupling reaction between N,N-bis（2-chloroethyl）aniline and 3-nitro-4-aminobenzcnic acid.The hyperbranched polymers（PBAA and PBANA） were prepared through nucleophilic substitution reaction of BAA and BANA, respectively.The polymers synthesized were characterized by using spectroscopic methods and thermal analysis.The photoinduced dichroism and photo-induced surface-relief-grating（SRG） formation of the hyperbranched polymers were investigated upon irradiation with Ar⁺ laser at 488 nm.PBAA shows typical photoinduced dichroism SRG formation behavior.On the contrary,PBANA does not show the photoresponsive properties.The results indicate that the nitro at the ortho position of azo group of PBANA shows the effect of inhibiting the photoinduced variations.The effect can be attributed to the blockage of the trans-cis isomerization of the azobenzene moieties by the steric hindrance.     

Preparation and characterization of hyperbranched polyaspartimides from bismaleimides and triamines

Hyperbranched polyaspartimides were successfully prepared from bismaleimides (A₂) and triamines (B₃) through the Michael addition reaction. Two bismaleimides of 4,4′‐bismaleimidodiphenylmethane (BMDM) and bis(3‐ethyl‐5‐methyl‐4‐ maleimidophenyl)methane (BEMM) and two triamines of tris(3‐aminophenyl)phosphine oxide (TAPPO) and tris(4‐aminophenyl)amine (TAPA) were employed in the preparation of these hyperbranched polyaspartimides. The chemical structures of the polymers were characterized with Fourier transform infrared (FTIR), ¹H and ³¹P NMR, and elemental analysis. Degrees of branching ranging from 0.51 to 0.69 were found with the polyaspartimides, ensuring their hyperbranched structure. The polymers also showed good solubility in common solvents, high glass‐transition temperatures of 256 °C, and excellent thermal stability above 370 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5921–5928, 2004     

Synthesis of hyperbranched poly(ester urethane isocyanates) and their derivatives

Hyperbranched poly(ester urethanes) containing end isocyanate groups have been synthesized via the reaction of hyperbranched aliphatic polyesterpolydiols of three generations with tolylene diisocyanate. The interaction of these compounds with N,N-dimethylaminoethanol yields their functional derivatives. The polymers are characterized by functional analysis, ¹H NMR and IR spectroscopy, and DSC. It has been demonstrated that the incorporation of urethane moieties leads to development of the microheterogeneous structure of hyperbranched polymers.     

Synthesis and second-order nonlinear optical properties of a crosslinkable functionalized hyperbranched polymer

A new implementation of copper-free thermal Huisgen 1,3-dipolar crosslinking reaction into a high T_g hyperbranched polyimide polymer in order to stabilize the electro-optic (EO) activity of second-order non linear materials is reported. Towards this goal, two different synthetic approaches were explored. The first strategy is based on the post-functionalization of the polymer with mixtures of DR1 azido derivative and propargylic alcohol, whereas, the second consists in the preparation of two complementary functionalized hyperbranched polymers that are mixed just before the preparation of films. Materials exhibit good second-order nonlinear optical coefficients (d₃₃) close to 30 pm/V at the fundamental wavelength of 1064 nm. Moreover, the thermal stability of the NLO properties of these materials reaches temperatures as high as 150 °C, and probably higher. This represents the highest thermal stability of crosslinkable EO polymers based on the crosslinking Huisgen reaction.     

Synthesis and properties of polyurethane elastomers crosslinked with amine-terminated AB2-type hyperbranched polyamides

Amine-terminated AB₂-type hyperbranched polyamides of different molecular weights were prepared from 3,5-bis-(4-aminophenoxy)benzoic acid (AB₂ monomer) by fractional precipitation technique and characterized by FTIR, ¹H-NMR spectroscopies, DSC and GPC techniques. The degree of branching (DB) of hyperbranched polymers (HBP) was determined using ¹³C-NMR spectroscopy and it was found that the value increased with decrease in molecular weight of polymer considered. As the molecular weight distribution was narrow, the approximate number of end functional groups of each HBP was conveniently calculated. Three polymers were selected and used as crosslinkers in the preparation of polyurethanes. The incorporation of hyperbranched polyamide into the polyurethane chains was confirmed using FTIR and ¹H-NMR spectroscopic techniques. Among the range studied (1-6%), it was found that high tensile strength is attained with 1% of HBP. It was also found that the tensile strength decreases with increase in number of end functional groups and decrease in DB of HBP. However, glass transition temperatures and thermal stability of polyurethanes crosslinked with up to 6% of HBP, above which gelation occurred, were not affected and similar to the blank polymer prepared without AB₂ polymer.