Sebacoyl Chloride Research Articles

Degradation Studies of Polycaprolactone in Banana Fibers Reinforced Thermoplastics Composites

In this paper we report the fabrication, properties and degradation studies of banana fibers–reinforced thermoplastic polymers. In order to impart hydrophobicity to the fibers and also to concomitantly increase interfacial bond strength, which is a critical factor for obtaining better mechanical properties of composites, banana fibers were treated with sodium hydroxide (5% and 10% for 4 h), sebacoyl chloride (SC) (0.5 g, 4 h), or toluene diisocyanate (TDl) (1.5 mL, 4 h). Mechanical properties of banana fibers treated with TDl were not affected to any significant extent, but there was an increase in tensile strength of fibers treated with sodium hydroxide (NaOH). Deterioration in mechanical properties was observed upon SC treatment. In thermograssimetre analogue (TGA) studies fibers showed initial mass loss (6.5%–9.5%) in the 50–150°C temperature region. Major weight loss occurred above 200°C. Scanning electron microscope (SEM) studies revealed an increase in surface roughness after alkali treatment. High density polyethylene (HDPE) modified by blending with poly (ε‐caprolactone) (80:20 w/w) was used as a thermoplastic matrix. Composites were fabricated by using 1 cm long banana fibers; the weight fraction of fibers was varied from 0.05–0.13. An increase in weight fraction of fibers resulted in an increase in tensile strength and modulus and decrease in elongation at break. Thin sheets and dumbbells were used for enzymatic and chemical hydrolysis degradation tests. The degradation of the material was monitored by weight change and loss of mechanical properties. The enzymatic degradation in (PCL) presence of Pseudomonas cepacia lipase (PCL) gave appreciable weight loss in PCL and blended materials.

Molecular design, synthesis, and electro‐optic properties of novel Y‐type polyesters with high thermal stability of second harmonic generation

Abstract3,4‐Di‐(2′‐hydroxyethoxy)‐4′‐nitrostilbene was prepared and condensed with terephthaloyl chloride, adipoyl chloride, and sebacoyl chloride to yield novel Y‐type polyesters containing NLO‐chromophore dioxynitrostilbenyl groups, which constituted parts of the polymer backbone. Polymers were found soluble in common organic solvents such as acetone and N,N‐dimethylformamide. They showed thermal stability up to 300 °C in thermogravimetric analysis with glass‐transition temperatures obtained from differential scanning calorimetry in the range 110–152 °C. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at a 1064 cm−1 fundamental wavelength were around 3.51 × 10−8 esu. The dipole alignment exhibited high thermal stability even at 10 °C higher than the glass‐transition temperature, and there was no SHG decay below 120 °C for one of these polymers due to the partial main‐chain character of polymer structure, which was acceptable for NLO device applications. Copyright © 2005 Society of Chemical Industry

Main‐chain chiral smectic liquid‐crystalline ionomers containing sulfonic acid groups

AbstractThree series of main‐chain liquid‐crystalline polymers (P1, P2, and P3) were synthesized by an interfacial condensation reaction of sebacoyl dichloride with various amount of brilliant yellow, isosorbide, and 4,4′‐biphenydiol. P1 series are polyesters prepared from sebacoyl chloride and various amount of 4,4′‐biphenyldiol and isosorbide. P2 series are polyesters prepared from sebacoyl chloride and various amount of 4,4′‐biphenyldiol, brilliant yellow, and isosorbide. P3 series are polyesters prepared from sebacoyl chloride and various amount of 4,4′‐biphenyldiol and brilliant yellow. P2 and P3 are main‐chain liquid‐crystalline ionomers. P12 and P3 series were prepared as model polymers for comparison with the liquid crystalline behavior of ionomers, P2 series. The structures of the polymers were characterized by IR and UV spectroscopy. Differential scanning calorimetry was used to measure the thermal properties of the polymers. The mesogenic properties were investigated by polarized optical microscope, differential scanning calorimetry, and X‐ray diffraction measurements. The results show that P2 series are chiral smectic C (SmC*) and chiral smectic B (SmB*) liquid crystalline ionomers exhibiting broken focal‐conic texture and schlieren, as is the polymer P12, which has the same amount of 4,4′‐biphenydiol and isosorbide. The introduction of ionic units in P2 series leads to an increase of clearing point, but has not affected the mesogenic type and texture, as compared with the corresponding polymer P12. The introduction of chiral units in P2 series leads to a change of mesophase, as compared with P3 series, which exhibit smectic C mesogetic phase. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1254–1263, 2006

Silica/Polyamide Nanocomposite Synthesis via an Original Double Emulsification Process in Miniemulsion

AbstractSummary: A new method for the encapsulation of inorganic charges by an organic polymer by a reactive double emulsification process is proposed. This work is especially novel since it is highly unusual to encounter polymerization reactions in such a double emulsification process. Silica was first synthesized in cyclohexane using a sol–gel process in an inverse microemulsion in the presence of a non‐ionic surfactant (nonylphenyl ether polyoxyethylene), tetraethoxysilane, and concentrated ammonia. The coupling agent, 3‐aminopropyl triethoxysilane, was then grafted onto the surface of the silica nanoparticles. In a third step, direct miniemulsions were prepared from the microemulsion containing the functionalized silica nanoparticles. The miniemulsions were prepared using sodium dodecylsulfate as the surfactant and cetyl alcohol as the costabilizer. Finally, an interfacial polycondensation occurred between a diamine added to the external phase and sebacoyl chloride in solution in the dispersed phase. The formation of polyamide latexes was proven using infrared spectroscopy, and observation of the nanocomposites by transmission electron microscopy showed mean diameters of 100 nm.TEM micrograph of silica/polyamide nanocomposite particlesmagnified imageTEM micrograph of silica/polyamide nanocomposite particles

Synthesis of Hydroxymethyl-Functionalized Polyimides and the Facile Attachment of an Organic Dye Utilizing Bis(isocyanates) and Bis(acid chloride) Linkers

Two new monomers were prepared of the formula 3,X-bis(4-aminophenoxy)benzenemethanol (where X = 5, 3a; X = 4, 3b) and each copolymerized with 2,2-bis(4-aminophenyl)hexafluoropropane, 6-FDA, and 6 mol % of phthalic anhydride as an end-cap to afford polyimides 4 and 5, respectively. The CH2OH group in the polymers could be modified with excess 1,6-hexanediisocyanate to afford 100% modification of polymer 6 concomitant with formation of a pendent and reactive isocyanate group. This latter polymer was shown to react with disperse red 1 (DR-1) to produce a polyimide-supported dye (7, Tg 199 °C) via formation of a urethane linkage. Treatment of the polymers 4 and 5 with excess adipoyl chloride afforded polymers 8 and 9, respectively, with a pendent acid chloride functional group. Further reaction with disperse red 1 (DR-1) in the presence of DMAP led to rapid esterification, yielding high-Tg dye-attached polyimides 11 (Tg 168 °C) and 12 (Tg 175 °C). Treatment of polymer 4 with sebacoyl chloride (a longer spacer...

The preparation and properties of segmented‐chain liquid crystalline polyesters based on 4,4′‐dihydroxybiphenyl by interfacial polycondensation

AbstractThermotropic homopolyesters were prepared through interfacial polycondensation of 4,4′‐dihydroxybiphenyl with sebacoyl chloride. The optimal conditions of the process, in terms of the best yield, were studied through investigating the type of organic phase, amount of phase transfer agent, time and temperature of reaction, and volume ratio of aqueous to organic phase. The structure of the sample that had the best yield (53.235% ± 5%) was determined by means of elemental analysis, infrared spectra, and X‐ray. The effect of the molar ratio of the monomers on the yield and inherent viscosity was investigated. The inherent viscosity of the samples varied between 0.095 and 0.25 dL/g. The mesophase formed at elevated temperatures was studied by differential scanning calorimetry, polarized light microscopy, and depolarizing transmittance measurements. Our observations revealed that poly(4, 4′‐diphenyl sebacate), in contrast to previous reports that suggest this polymer is smectgenic, could produce nematic phase. It could be concluded that the chemical structure ordering of the poly(4, 4′‐diphenyl sebacate) plays a significant role in its liquid crystalline behavior. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1594–1606, 2005

Naphthalene-ring containing diamine and resulting thermally stable polyamides

A new naphthalene-ring containing diamine, bis-[4-(5-amino-naphthalene-1-yloxy)-phenyl]-methanone was prepared from reaction of 5-amino-1-naphthol with 4,4′-dichlorobenzophenone in the presence of K 2CO 3. A series of novel polyamides were prepared by direct polycondensation of the diamine with various commercially available diacid chlorides including terephthaloyl chloride, isophthaloyl chloride, adipoyl chloride, and sebacoyl chloride. All the synthesized polyamides showed good solubility in amide type solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, and N, N-dimethylformamide and they exhibited inherent viscosities in the range of 0.44–0.52 dL/g. According to the DMTA analysis, the glass transition temperatures of the polyamides were found to be 131–187 °C. Thermogravimetric analysis indicated that the polymers were stable up to 190 °C and the 10% weight loss temperatures were recorded in the range of 350–418 °C in air atmosphere.

Synthesis of biodegradable poly(ester amide)s containing functional groups

Novel poly(ester amide)s containing functional groups were prepared by polycondensation of diamine, diol, and sebacoyl dichloride. Benzyl-protected dimethylolpropionic acid was selected as the diol unit and the diamine was derived from hexanediol and glycine.

Synthesis of phenazine derivatives for use as precursors to electrochemically generated bases

1,6-Disubstituted phenazine derivatives for use as precursors to electrochemically generated bases have been synthesized from readily available starting materials. Reaction of 1,6-dihydroxyphenazine with 1,10-diododecane, 1,11-diiodo-3,6,9-trioxaundecane or (R,R)-(-)-1,2-bis(3-iodopropoxy)cyclohexane gave planar chiral phenazinophanes containing ether-linked bridges; molecular structures of all these compounds have been determined by X-ray crystallography. Substituted 1,6-diaminophenazines were prepared by palladium-mediated amination of 1,6-dichlorophenazine and acylation of 1,6-diaminophenazine followed by reduction. Reaction of 1,6-bis(alkylamino)phenazines with sebacoyl chloride gave planar chiral phenazinophanes containing amide-linked bridges.

Multiblock Copolymers of l-Lactide and Trimethylene Carbonate

Sequential copolymerizations of trimethylene carbonate (TMC) and l-lactide (LLA) were performed with 2,2-dibutyl-2-stanna-1,3-oxepane as a bifunctional cyclic initiator. The block lengths were varied via the monomer/initiator and via the TMC/l-lactide ratio. The cyclic triblock copolymers were transformed in situ into multiblock copolymers by ring-opening polycondensation with sebacoyl chloride. The chemical compositions of the block copolymers were determined from (1)H NMR spectra. The formation of multiblock structures and the absence of transesterification were proven by (13)C NMR spectroscopy. Differential scanning calorimetry (DSC), wide-angle X-ray scattering (WAXS), and dynamic mechanical analysis (DMA) measurements confirmed the existence of a microphase-separated structure in the multiblock copolymers consisting of a crystalline phase of poly(LLA) blocks and an amorphous phase formed by the poly(TMC) blocks. Stress-strain measurements showed the elastomeric character of these biodegradable multiblock copolymers, particularly in copolymers having epsilon-caprolactone as comonomer in the poly(TMC) blocks.

Charge transfer interactions in polyesters with a donor‐(σ‐bridge)‐acceptor moiety in the repeating unit

AbstractTwo high molecular weight linear polyesters were investigated to gain insight in how the photophysics of electron donor‐(σ‐spacer)‐electron acceptor (DσA) compounds are affected by incorporation into a polymer. They were prepared by condensation of either adipoyl or sebacoyl chloride with a diol that was functionalized with an N,N‐dialkylaniline donor, a cyclohexyl type σ‐spacer, and a 1,1‐dicyanovinyl acceptor. The solubility, which is very low, and the thermal properties of the polyesters are dictated by physical crosslinking as a consequence of interchain donor‐acceptor interactions. Charge transfer (CT) absorption and emission are observed, which involve CT between DσA moieties of different chains rather than CT processes within a single DσA unit. As a result, the photophysics of the DσA units in the polyesters differs strongly from that of similar DσA compounds in solution. Upon swelling the polymers with THF, the CT fluorescence disappears partly. Analogous polymers containing only an N,N‐dialkylaniline donor display dual fluorescence; one band reflects local emission, while the other is attributed to excimer emission. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4775–4784, 2004

Synthesis and characterization of new polyamides derived from 4-(4?-aminophenyl)urazole and aliphatic diacid chlorides

4-(4′-Aminophenyl)urazole (AmPU) was prepared from 4-nitrobenzoic acid in six steps. The reaction of AmPU with acetyl chloride was performed in N,N-dimethylacetamide solutions at different ratios, and the resulting disubstituted and trisubstituted amide derivatives were obtained in high yields and were used as models for polymerization reactions. Polycondensation reactions of AmPU with succinyl chloride, suberoyl chloride, and sebacoyl chloride were performed with conventional solution polymerization techniques in the presence of different catalysts, such as pyridine, triethylamine, and dibutyltin dilaurate, and led to the formation of novel aliphatic polyamides. The resulting novel polyamides had inherent viscosities of 0.11–0.22 dL/g in dimethylformamide or H2SO4 at 25°C. These polyamides were characterized with IR, 1H-NMR, elemental analysis, and thermogravimetric analysis. Some physical properties and structural characterization of these novel polyamides are reported. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3173–3185, 2004

New Azobenzene Chromophores as Monomers for Synthesis of Polyesters

Two new azo-chromophores: 2,4-dihydroxy-4’-nitroazobenzene and 2,4-dihydroxy-4-azo-(4’-nitroazobenzeno)benzene have been prepared. These diols have been applied as monomers for polyesters synthesized in condensation with diacid chlorides: isophthaloyl chloride and sebacoyl chloride. The copolymers consist of mixture of two new diols and chlorides have been obtained as well. The polymers were identified by infrared and elemental analysis. Character of polymers was determined using X-Ray spectroscopy. Thermal properties of polyesters such as glass transition temperature and thermal stability were investigated using differential scanning calorimetry (DSC) method and thermogravimetric analysis. These polymers with azobenzene groups could find potential applications as holographic recording materials. The preliminary investigations of optical grating recording were carried out.

Preparation of polyesteramides based on aliphatic amine-containing phenol derivatives via interfacial polymerization

A series of polyesteramides with randomly introduced ester/amide group ratio of 50/50 were newly synthesized by reacting terephthaloyl chloride, isophthaloyl chloride and sebacoyl chloride with tyramine and tyrosine. The polymerization was carried out by interfacial polymerization in two phase solvent systems, which gave various polyesteramides with moderate molecular weights in good yields. The chemical structures of the polymers were confirmed by1H NMR, IR and elemental analysis. Tyrosine based polyesteramide was degraded thermally around 290°C to give the polyesteramide, which was obtainable from tyramine. Thermal stability and degradation behaviors were examined by differential scanning calorimetry and thermogravimetric analyses.

An approach to novel polyamidoamine (PAMAM) side chain dendritic polyesterurethane (SCDPEU) block copolymer architectures

A novel polyamidoamine (PAMAM) side chain dendritic polyesterurethane (SCDPEU) block architecture derived from ester terminated polyamidoamine dendritic diol (G2.3), sebacoyl chloride and 2,4-toluidene diisocyanate (TDI) is reported. This material was characterized by means of IR and NMR spectroscopies, as well as by intrinsic viscosity and differential scanning calorimetry measurements. SCDPEU synthesis was conducted in bulk by using the catalytic amount of dibutyl tin dilaurate (DBTDL).

Cellular interactions and degradation of aliphatic poly(ester amide)s derived from glycine and/or 4-amino butyric acid

A series of poly(ester amide)s derived from amino acid (glycine or 4-amino butyric acid), diol (1,6-hexanediol or 1,4-butanediol) and sebacoyl chloride were prepared by interfacial polymerization. FT-IR analysis indicated that for poly(ester amide)s derived from glycine, only amide–amide hydrogen bonds and hydrogen-bonded C=O ester groups were established, whereas the poly(ester amide)s derived from 4-amino butyric acid contained amide–amide hydrogen bonds and amide–ester hydrogen bonds, including NH groups and C=O ester groups in free state. The biodegradability was estimated by weight residue of poly(ester amide) films in pH 6 buffer solution with papain at 37°C. The poly(ester amide) films derived from glycine demonstrated significantly improved degradability compared to the poly(ester amide) films derived from 4-amino butyric acid. This difference of degradation rate could be explained by the bonding state in C=O ester groups. The cellular interaction of the poly(ester amide)s was studied by measuring the proliferation of human dermal fibroblasts on the polymer films. The cells proliferated significantly faster on poly(ester amide) films derived from 4-amino butyric acid than on poly(ester amide) films derived from glycine. These results suggest that the poly(ester amide) prepared in this study may serve as a potential cell-compatible biomedical material.

Preparation of oily core polyamide microcapsules via interfacial polycondensation

AbstractMicrocapsules obtained by interfacial polycondensation from an original system based on the polyaddition of specific di‐ or polyamines and more classical acyl chloride molecules were studied. The originality of the system lies in the fact that the encapsulated agent is the internal phase allowing its incorporation without an organic solvent, which is an advantage from the point of view of environmental protection. Once the optimal parameters of the emulsion were determined, the membrane formation was studied by optimizing the emulsification and reaction times in relation to simultaneous acyl chloride hydrolysis. The microcapsules were obtained by interfacial polycondensation between an excess of amine functions (diamine and diethylenetriamine) and acyl chloride (sebacoyl chloride and 1,3,5‐benzene tricarbonyl trichloride) from an oil‐in‐water emulsion in the presence of 88% hydrolyzed poly(vinyl alcohol) as a surfactant. Various formulations in terms of COCl concentration, crosslinking agent concentration, excess of amine functions, emulsification and reaction times were prepared. The hydrolysis of acyl halide functions is the main parameter which influences the growth of the membrane. The increase in acyl chloride function concentration allows compensation for that lost by hydrolysis, and increases the encapsulation yield to about 90%. The degree of crosslinking of the membrane was controlled in order to minimize the subsequent release of oil by the addition of trifunctional monomers. An optimal formulation was developed offering high encapsulation yield and optimal elastic behaviour. Almost spherical capsules, with a membrane thickness of approximately 500 nm, relatively smooth internal walls and crumpled external walls, were observed by scanning electron microscopy.© 2003 Society of Chemical Industry

Synthesis and characterization of novel soluble and thermally stable polyamides based on pyridine monomer

AbstractNucleophilic aromatic substitution reaction of 4‐aminophenol and also 5‐amino‐1‐naphthol with 2,6‐dichloropyridine in N‐methyl‐2‐pyrrolidone (NMP) as solvent, in the presence of potassium carbonate, afforded two aromatic ether diamines. Eight soluble, thermally stable polyamides were prepared by polycondensation reaction of the obtained diamines with aromatic and aliphatic diacid chlorides including terephthaloyl chloride (TPC), isophthaloyl chloride (IPC), adipoyl chloride (AC), and sebacoyl chloride (SC). The prepared monomers and polymers were characterized by conventional spectroscopic methods. Physical and thermal properties of the polymers, such as thermal behavior, thermal stability, solution viscosity, and solubility behavior were also studied.

Biodegradable micelles/polymersomes from fumaric/sebacic acids and poly(ethylene glycol)

Linear unsaturated oligo-anhydrides containing terminal acylchloride groups have been synthesized by polycondensation of fumaric or sebacic acid with either fumaryl chloride or sebacoyl chloride. Reaction of these oligo-anhydrides with poly(ethylene glycol) produce di- and tri-block copolymers. The oligo-anhydrides and block copolymers have been characterized by gel permeation chromatography (GPC), NMR and FT-IR spectroscopies. The tri-block copolymers composed of two PEG end blocks and an oligo-anhydride center block have been used in encapsulation of calcein (encapsulation efficiency up to 40%). Encapsulation and release profile of calcein (as a model hydrophilic drug) from the di-block copolymers (micelles) and tri-block copolymer vesicles (polymersomes) as well as their in-vitro hydrolytic degradation (pH=7.4°C, 37°C) are reported.

Syntheses of biodegradable (multi) block copolymers, star‐shaped polyesters and networks via ring‐expansion polymerization

AbstractNumerous cyclic dibutyltin alkoxides were prepared by condensation of Bu2Sn(OMe)2 with various short or long α,ω‐diols. Insertion of lactones or lactide into the SnO bonds resulted in ring‐expansion polymerizations which allowed a control of the ring size (chain length) via the monomer initiator ratio. When the cyclic initiators were derived from a long α,ω‐diol, such as poly(tetrahydrofuran)diols or polysiloxane diols, the resulting cyclic polylactones were necessarily cyclic triblock copolymers. The high nucleophilicity of the Sn‐O bond enabled ring‐opening polycondensations with dicarboxylic acid dichlorides yielding multiblock copolyesters. Condensations with monocarboxylic acids yielded functionalized A‐B‐A triblock copolymers. Polycondensation with trifunctional acid chlorides yielded biodegradable networks. Hydroxyethylated pentaerythritol condensed with Bu2Sn(OMe)2 yielded a spirocyclic initiator. Ring‐expansion polymerization with lactones followed by acylation with carboxylic acid chlorides produces star‐shaped polylactones having functional endgroups. Biodegradable networks were also obtained when bisstannylenated α‐glucose methyl glycoside was used as initiator for ϵ‐caprolactone, and when the resulting spirocyclic polylactone was polycondensed with sebacoyl chloride. Copyright © 2003 John Wiley & Sons, Ltd.