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Branched polyesters with acid degradable and oxidation responsive β-thiopropionate groups have been obtained by lipase catalyzed polycondensation of diester and hydroxyester monomers from heptanal, a castor oil derivative. Their polymerization behavior has been investigated and poly(ethylene glycol)-b-poly(β-thioether ester) amphiphilic block copolymers have been obtained. SEC, NMR and FTIR have been employed to confirm the structure of the polymers and copolymers and DSC and TGA have been used to characterize their thermal properties. The block copolymers containing aliphatic pendant moieties self-assemble into micelles in aqueous solution, showing potential application as dual responsive systems in drug delivery.

Intensive research has recently been carried out to synthesize non-isocyanate polyurethanes (NIPUs) from five-membered cyclic carbonates and amines as a sustainable route to industrial relevant polyurethanes. Herein, an activated disubstituted cyclic carbonate and methyl ester containing monomer CE was prepared using castor oil based heptanal and CO 2 . Good results for the catalytic cycloaddition have been obtained using renewable sugar cane bagasse in combination with TBAB, and this system has been shown to be recyclable. A novel poly(amide-hydroxyurethane) ( PAHU ) was obtained by bulk ring-opening and amidation polymerization of high reactive CE with 1,6-diaminohexane at low temperature and in absence of catalyst. PAHU contains aliphatic pendant moieties allowing its self-assembling into nanoparticles in aqueous solution, showing potential application in catalysis or drug delivery among other applications.

The synthesis and characterization of fully biobased ABA triblock copolyesters from PLA and castor oil derivatives are described. The synthetic strategy uses a dihydroxy telechelic polyester as a macroinitiator for the ring opening polymerization of l -lactide. This macroinitiator was obtained from a sulfur-containing hydroxyacid derivative of 10-undecenoic acid, which undergoes self-polycondensation with low amounts of biobased 1,4-butanediol, enables the obtention of two prepolymers of different weight. Two series of triblock copolyesters with different percentage of PLA contents were prepared and the resulting thioether-bearing copolyester oxidized to polysulfones. Both series of copolyesters showed improved thermal stability, decrease of crystallinity and a similar hydrophilicity with respect to the PLA homopolymer.

A set of thermoplastic polyurethanes is synthesized, combining undecylenic acid-derived telechelic diols as soft segments and 1,4-butanediol/4,4'-methylenebis(phenylisocyanate) as a hard segment (HS). These polymers are fully chemically and physically characterized by means of NMR and Fourier transform IR (FTIR) spectroscopy, size-exclusion chromatography (SEC), DSC, thermogravimetric analysis (TGA), tensile testing, and contact angle measurements. The obtained results reveal that both the molecular weight of the diol and the HS content greatly influence the physical and mechanical properties of these polymers. In addition, given the potential use of these materials for biomedical applications, hydrolytic degradation, their biocompatibility using a human fibroblast cell line, and performance as drug delivery carriers are evaluated.

In this chapter we present synthetic strategies to incorporate flexible segments into polybenzoxazine precursors such as monomers, oligomers, and polymers. In this way, a new class of flexible thermoset polybenzoxazines, with thermal and mechanical properties and enhanced processability, has been developed, allowing for potential new applications for these polymers. Strategies successfully employed include monomer and polymer synthesis based on Mannich, hydrosilylation, metathesis, classical polycondensations, and Huisgen type click reactions.

A polybenzoxazine / polysiloxane hybrid has been prepared by sol-gel process and ring-opening polymerization. For this purpose, first a functionalized benzoxazine was synthesized from bisphenol A, paraformaldehyde and 3(trimethoxysilyl) propylamine, with initial molar ratio 1:4:2, and 95% yield. The structure of the monomer was characterized by Fourier Transform Infrared, Spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR). The sol-gel process and curing behavior have been studied by FTIR spectroscopy and Differential Scanning Calorimetry (DSC). The Dynamic Mechanical Analysis (DMTA) of the hybrid material(Bz-PSi) showed higher Tg and storage modulus respect to the conventional polybenzoxazine (Bz-BA). Also, the Thermogravimetric Analysis (TGA) revealed better thermal stability. The high Limiting Oxygen Index (LOI) values (about LOI = 32)confirmed similar effective flame retardance properties of the hybrid material respect conventional benzoxazine. Fil: Spontón, Marisa Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Estenoz, Diana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Ligadas, G.. Universitat Rovira I Virgili; España Fil: Ronda, J.. Universitat Rovira I Virgili; España Fil: Galià, M.. Universitat Rovira I Virgili; España Fil: Cádiz, V.. Universitat Rovira I Virgili; España

Fast-degrading linear and branched polyanhydrides are obtained by melt-condensation of novel di- and tri-carboxylic acid monomers based on oleic and undecylenic acid synthesized using photoinitiated thiol-ene click chemistry. (1)H NMR spectroscopy, size exclusion chromatography, differential scanning calorimetry, thermogravimetric analysis, and FT-IR spectroscopy have been used to fully characterize these polymers. The hydrolytic degradation of these polymers was studied by means of weight loss, anhydride bond loss, and changes in molecular weight, showing fast degrading properties. Drug release studies from the synthesized polyanhydrides have also been conducted, using rhodamine B as a hydrophobic model drug, to evaluate the potential of these polymers in biomedical applications.

Two different approaches to the creation of phosphorus-containing soybean-oil copolymers were investigated. First, two phosphorus-containing styrene (ST) derivatives, diphenyl styryl phosphine oxide and dimethyl-p-vinylbenzylphosphonate (STP2), where tested as comonomers in the cationic copolymerization of soybean oil (SOY), ST, and divinylbenzene (DVB), to obtain heterogeneous systems in all cases. To overcome this drawback, the cross-metathesis reaction of methyl 10-undecenoate and STP2 was carried out to link the phosphorus moiety to the vegetable-oil derivative. This second approach permitted the synthesis of a new reactive phosphorus-containing plant-oil derivative, which was incorporated into the soybean oil, ST, and DVB system. The cationic copolymerization was investigated, and the structure, thermal stability, and mechanical and flame-retardant properties of the resulting copolymers were studied. Thermosets with moderate glass-transition temperatures were obtained; this showed that the cross-metathesis reaction is a convenient way to produce oil-compatible monomers able to undergo homogeneous polymerization reactions. The resulting thermosets with 1% phosphorus had limiting oxygen index values about 24.0; this indicated an improvement in the fire-retardant properties of the soybean-oil-based copolymers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The first example of boron-containing soybean oil based copolymers was prepared from soybean oil, styrene, divinylbenzene and 4-vinylphenyl boronic acid by cationic polymerization using boron trifluoride etherate as initiator. Soxhlet extraction and NMR spectroscopy indicate that the copolymers consist of a crosslinked network plasticized with varying amounts of oligomers and unreacted oil. The thermal degradation mechanism was studied and the thermal, dynamomechanical and flame retardant properties of these materials were examined. Thermosets with glass transition temperatures ranging from 43 to 60 °C, which are thermally stable below 350 °C and with LOI values from 23.7 to 25.6 were obtained. The LOI tests indicate that the flame retardant properties of vegetable oil can be improved by adding boron covalently bonded to the polymer.

The acyclic diene metathesis polymerization (ADMET) of 1,3-di-10-undecenoxy-2-propanol, a castor oil based diene, is reported. 10-Undecenol was used as renewable comonomer to end-cap polymer chains and limit the molecular weight. The poly ols obtained in this way were reacted with 4,4′-methylenebis(phenylisocyanate) (MDI) to yield a series of amorphous and semicrystalline polyurethane networks. The thermal stability and the thermomechanical and mechanical properties of these thermosets have been studied and showed good shape memory properties for the semicrystalline polymer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

A series of poly(ether urethane) networks were synthesized from polyether polyols obtained by ionic-coordinative polymerization of epoxidized methyl oleate (EMO) using 4,4′-methylenebis(phenyl isocyanate) or l-lysine diisocyanate as coupling agents. Moreover, a variety of segmented poly(ether urethane) networks with different hard segment contents were obtained using 1,3-propanediol as the chain extender. The materials were characterized by differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical thermal analysis, and tensile properties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

Novel composite asymmetrical membranes based on poly(vinyl alcohol)-co-ethylene (EVAL) as the host material and new polyethers that contain azobenzene moieties in the side chain were prepared by dry-cast phase inversion after dissolving the azo polymers in tetrahydrofuran and EVAL in dimethylsulfoxide and subsequently mixing the resulting solutions. By taking advantage of the proper temperature variation in the oven used for solvent evaporation, asymmetrical membranes that exhibited a dense, crystalline layer on the bottom and a porous, mainly amorphous layer on the top were obtained. Remarkable changes in the surface morphology and the contact angle with water were observed on the top surfaces of the composite membranes. This was ascribed not only to the enhanced concentration of azo polymer on the top surface but mostly to a conformational change in EVAL induced by the photoisomerization of the guest azo groups, as shown by HRMAS (1)H NMR. The morphological and structural changes in EVAL could be reversed on exposing the membrane to visible light for 24 h.

The fire retardance and thermal stability of soybean-based copolymers reactively modified by copolymerization with trimethylsilylstyrene (SiST) and tris-(4-vinylphenylboroxine) (BST) have been compared with those prepared with equivalent amounts of the additive 1,3-diphenyl-1,1,3,3-tetramethyldisiloxane (SiAD) and tris-(phenylboroxine) (BAD) and with the heteroatom-free soybean-based copolymers. The best results are obtained for the boron-containing copolymers. The reactive or additive approach is a significant factor in terms of the level of fire retardance achieved.

Soybean oil is one of the most promising renewable raw materials for polymers. Cationic copolymerization with a variety of olefinic monomers gives interesting materials but the curing process is tedious and high temperatures and long reaction times are needed. We studied the cationic homopolymerization of soybean oil and its copolymerization with styrene and divinylbenzene under microwave irradiation using boron trifluoride etherate as initiator and the comparison with conventional heating showed a great enhancement in reaction rates.

Vegetable oils are excellent renewable raw materials for thermosetting polymers. By the direct polymerization of triglyceride C=C, we obtained organic-inorganic hybrid materials with promising properties for optical applications by the hydrosilylation of alkenyl-terminated fatty acid derivatives. The presence of double bonds in triglycerides makes it possible to attach some functional groups through chemical modification, and we describe various chemical pathways for functionalizing triglycerides and fatty acids. Epoxidation is one of the most interesting chemical modifications that leads to epoxidized vegetable oils. We report the preparation of biobased polyhedral oligomeric silsesquioxanes-nanocomposites from epoxidized linseed oil. Moreover, we describe the preparation of a new family of epoxidized methyl oleate-based polyether polyols, which were used in the synthesis of polyurethanes with specific applications: silicon-containing polyurethanes with enhanced flame-retardant properties and polyurethane networks with potential applications in biomedicine. An enone-containing triglyceride derivative was obtained, by an environmentally friendly chemical procedure from high oleic sunflower oil that could be cross-linked with diamines. In a similar way, triglycerides containing secondary allylic alcohols can be obtained that can be further functionalized with acrylate or phosphorus-containing derivatives to obtain flame-retardant thermosets.

Two new polyethers, bearing azobenzene moiety in the side chain, were synthesized in excellent yields by means of anionic polymerization of 4-glycidyloxyazobenzene and 4-cyano-4′-glycidyloxyazobenzene (leading to azo-P1 and azo-P2 polymers, respectively) with the system polyiminophosphazene base t-Bu-P4/3,5-di-tert-butylphenol as initiator. The polymers were characterized with respect to their molecular weights, structure, and calorimetric features. The polyether bearing cyanoazobenzene group in the side chain was found to exhibit nematic phase up to 200 °C. E–Z isomerization of both polymers in tetrahydrofuran solution, after irradiating with UV light at 364 nm for 15 min, was investigated by means of UV–visible absorption spectroscopy. In the case of glycidylic monomers as well as the resulting polymers, E–Z isomerization was also investigated by means of 1H NMR, by direct irradiation in the NMR probe in deuterated 1,1,2,2-tetrachloroethane solution. By this technique, in the case of 4-cyano-4′-glycidyloxyazobenzene, it was found that irradiation led to a photostationary state corresponding to an amount of Z isomer equal to 25%. For azo-P1 polymer, Z–E or “reverse” isomerization was investigated at 60, 70, or 80 °C directly in the NMR probe; as expected, the process followed a first-order rate law. The kinetic constants as well as the activation energy for the process were determined in this temperature range. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5426–5436, 2009

DOPO-containing benzoxazine, which could not be prepared by the traditional approaches, was successfully prepared from phenol, aniline and DOPO by a three-step procedure. The first step is the condensation of 2-hydroxybenzaldehyde with aniline, forming an intermediate imine. The second step is the addition of DOPO to the imine resulting a secondary amine. The third step is the ring closure condensation leading to DOPO-containing benzoxazine. All these structures were confirmed by 1D and 2D NMR spectra. The curing of mixtures of DOPO-containing benzoxazine and benzoxazine of Bisphenol A has been studied. In the samples the molar ratio of benzoxazine monomers was varied to achieve different phosphorus content. The phosphorus-containing polybenzoxazines have been characterized by dynamicmechanical thermal analysis and thermogravimetric analysis. Limiting oxygen index values indicate good flame retardant properties. Fil: Spontón, Marisa Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina. Universitat Rovira I Virgili; España Fil: Ligadas, G.. Universitat Rovira I Virgili; España Fil: Ronda, J. C.. Universitat Rovira I Virgili; España Fil: Galià, M.. Universitat Rovira I Virgili; España Fil: Cádiz, V.. Universitat Rovira I Virgili; España

Phosphorus-containing triglycerides were prepared from a new route that involves the singlet oxygen photo-oxygenation of high oleic sunflower oil and further reduction of the resulting hydroperoxide derivatives to a mixture of secondary allylic alcohols. These allylic alcohols in presence of chlorodiphenylphosphine give allylic phosphinites capable to undergo a [2,3]-sigmatropic rearrangement leading to tertiary phosphine oxides directly linked to triglyceride in a one-pot two-step reaction. The obtained phosphorus-containing triglycerides with different hydroxyl content were activated to polymerization by acrylation and these acrylate triglycerides were radically crosslinked in presence of different amounts of pentaerythritol tetra-acrylate. The thermal, dynamic-mechanical, and flame retardancy properties of the final materials were evaluated. Thermal and thermo-oxidative degradation was studied by gas chromatography/mass spectrometry, 31 P HR-MAS NMR spectroscopy, and scanning electron microscopy.

The copolymerisation of benzoxazine of bisphenol A and diglycidyl ether of (2,5-dihydroxyphenyl)diphenyl phosphine oxide or diglycidyloxymethylphenylsilane has been studied. In all samples the molar ratio of the benzoxazine–epoxy system was varied to achieve different phosphorus or silicon contents. Their thermal, dynamic-mechanical and flame retardant properties were evaluated. The high limiting oxygen index values confirmed that the phosphorus-containing benzoxazine–epoxy resins are effective flame retardants, but no efficiency of silicon on flame retardation was observed.

Triglycerides with acrylate functionality were prepared from a new route that involves the singlet oxygen photooxygenation of high oleic sunflower oil and further reduction of the resulting hydroperoxide derivatives to a mixture of secondary allylic alcohols. These unsaturated alcohols can be further reduced to saturated alcohols. These two new hydroxyl-containing triglycerides were functionalized as acrylate esters and radically crosslinked in presence of different amounts of pentaerythritol tetraacrylate. The crosslinking reactions were followed by FTIR spectroscopy and the thermal properties of the final materials were evaluated. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1159–1167, 2009

The combustion behaviour of phosphorus- and silicon-containing benzoxazine-epoxy systems has been studied by LOI and cone calorimetry giving a clear evidence that incorporation of 3.5% P into the benzoxazine-epoxy systems, resulted in flame retardation while the silicon-containing copolymer was found to have no improvement in the LOI and cone calorimeter data, with values similar to the polymers without heteroatom, thus indicating that the 3.9% silicon content has no flame retarding effect. The peak of heat release rate value is reduced significantly for the phosphorus-containing benzoxazine as a result a combination of condensed-phase and gas-phase mechanisms.The incorporation of phosphorus or silicon into the modified benzoxazine-epoxy system increases the smoke hazard and the CO emissions compared to the heteroatom-free system. Fil: Spontón, Marisa Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Ronda, J.. Universitat Rovira I Virgili; España Fil: Galià, M.. Universitat Rovira I Virgili; España Fil: Cádiz, V.. Universitat Rovira I Virgili; España

The curing of mixtures of bis( m -aminophenyl)methylphosphine oxide based benzoxazine and glycidylether or benzoxazine of Bisphenol A has been studied. In all samples the molar ratio of benzoxazine monomers or the benzoxazine–epoxy system was varied to achieve different phosphorus content. The phosphorus-containing polybenzoxazines have been characterized by dynamic mechanical and thermogravimetric analysis. Limiting oxygen index values indicate good flame retardant properties.

Phosphorus- and silicon-containing epoxy resins were prepared from (2,5-dihydroxyphenyl)diphenyl phosphine oxide (Gly-HPO), diglycidyloxy methylphenyl silane (DGMPS) and 1,4-bis(glycidyloxydimethyl silyl)-benzene (BGDMSB) as epoxy monomers and diaminodiphenylmethane (DDM), bis(3-aminophenyl)methyl phosphine oxide (BAMPO) and bis(4-aminophenoxy)dimethyl silane (APDS) as curing agents. Epoxy resins with different phosphorus and silicon content were obtained. Their thermal, dynamic mechanical and flame retardant properties were evaluated. The high LOI values confirmed that epoxy resins containing hetero-atoms are effective flame retardants, but a synergistic efficiency of phosphorus and silicon on flame retardation was not observed.

Bis(m-aminophenyl)methylphosphine oxide based benzoxazine (Bz-BAMPO) was obtained using a three-step synthetic method from the aromatic diamine and 2-hydroxybenzaldehyde as starting materials. The structure and purity of the monomer was confirmed by elemental analysis, FTIR, 1H NMR, 13C NMR and 31P NMR spectra. The curing kinetics of Bz-BAMPO was investigated by nonisothermal differential scanning calorimetry (DSC) at different heating rates and by FTIR spectroscopy. The isoconversional method was used to evaluate the dependence of the effective activation energy on the extent of conversion. The evolving factor analysis (EFA) method was applied to the spectroscopic FTIR data obtained in monitoring benzoxazine homopolymerizations. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7162–7172, 2008

The autocatalytic thermal polymerization behavior of three benzoxazine monomers containing carboxylic acid functionalities is reported. Several mixtures of these carboxylic monomers and 3-phenyl-3,4-dihydro-2H-1,3-benzoxazine were prepared and their thermal polymerization behavior was analyzed by differential scanning calorimetry. The acid character of these reactive monomers increases the concentration of oxonium species, thus catalyzing the benzoxazine ring opening reaction. In this way the polymerization temperature decreased by as much as 100 °C in some cases. The existence of decarboxylation processes at high temperatures has been established by FTIR-ATR and related to the increase in thermal stability observed by TGA in some cases. A relationship between the presence of carboxylic groups in the resulting materials and their flame retardancy behavior has also been established. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6091–6101, 2008

To evaluate the influence of the electronic effects on the polymerization temperature, we looked at several 3-phenyl-3,4-dihydro-2-H-1,3-benzoxazine monomers with electron-withdrawing or electron-donating groups in the 6 and 4' positions. The monomers were synthesized and characterized using different synthetic methods to achieve the best possible results. The thermal polymerization of these benzoxazine monomers was analyzed by differential scanning calorimetry, and the polymerization behavior and the polymer characteristics were related to the electronic character of the substituent and the polymerization mechanism.

A series of poly(ether urethane) networks were synthesized from epoxidized methyl-oleate-based polyether polyol and 1,3-propandiol using l-lysine diisocyanate as a nontoxic coupling agent. Polyurethanes with different hard segment contents were prepared to tune the final properties of the materials. The polyurethanes were fully chemically and physically characterized, including water uptake and in vitro hydrolytic degradation measurements. The weight loss of the polyurethanes was traced, and the changes in the surface morphology with the degradation time were examined by scanning electron microscopy. The experimental results revealed that the hard segment content is the main factor that controls the physical, mechanical, and degradation properties of these polymers. The observed diversity in material properties suggests that these polyurethanes may be useful for a wide range of biomedical polymer applications.

Phosphine oxide-containing epoxy resins were prepared from diglycidyl ether of (2,5-dihydroxyphenyl)diphenyl phosphine oxide and diglycidyl ether of bisphenol A by crosslinking with 4,4'-diaminodiphenylmethane. Several (2,5-dihydroxyphenyl)diphenyl phosphine oxide/diglycidyl ether of bisphenol A molar ratios were used to obtain materials with different phosphorus content. The properties of the thermosetting materials were evaluated by differential scanning calorimetry, dynamic mechanical analysis, thermogravimetric analysis, and limiting oxygen index and related to the phosphorus content. Thermal and thermooxidative degradation was studied by GC/MS, 31 P MAS NMR spectroscopy, and scanning electron microscopy. Limiting oxygen index values indicate good flame retardant properties that are related to the formation of a protective phosphorus-rich layer that slowed down the degradation and prevented it from being total.

A new oxazolidine derivative was obtained from phenol, 2-amino-2-methylpropane-1,3-diol and paraformaldehyde. The reaction of this novel oxazolidine diol with phenylisocyanate lead to a urethane model compound which can be polymerized thermally by oxazolidine ring opening to give a Mannich bridge structure. Linear segmented polyurethanes were prepared by reaction of different ratios of oxazolidine diol and commercial polyethylenglycol (M w ∼ 400) with 4,4'-methylenbis (cyclohexylisocyanate) (HMDI, 90% isomers mixture). The polyurethanes were thermally characterized and crosslinked by oxazolidine ring opening to obtain materials which showed improved thermal stability.

This study is concerned with the preparation and properties of a new class of bionanocomposites from renewable resources. Epoxidized linseed oil (ELO) and 3-glycidylpropylheptaisobutyl-T8-polyhedral oligomeric silsesquioxane (G-POSS) (2, 5, and 10 wt %) were cross-linked, and Fourier transform infrared spectroscopy (FTIR), dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) were employed to characterize the POSS-reinforced oil-based polymer networks. No POSS aggregates were observed for the 2 wt % G-POSS nanocomposite by SEM. POSS-rich particles with diameters of several nanometers were observed in the nanocomposites with 5 and 10 wt % G-POSS. Enhanced glass transition temperatures and storage moduli of the networks in the glassy state and rubber plateau were observed to be higher than those of the POSS-free oil based polymer network, due to the reinforcement effect of POSS cages.

Two novel difunctional styrenic monomers – 2,2-bis(4-vinylbenzyl)propane-1,3-diol and 5,5-bis(4-vinylbenzyl)-2-phenyl-[1,3,2] dioxaborinane – were synthesized and copolymerized to test the influence of boron on the properties of materials. They were characterized by elemental analysis, mass spectrometry, FTIR and 1 H, 13 C NMR spectroscopy. The copolymers with boron showed higher thermal stability and char yields than polystyrene or homologous copolymers without boron. The thermal degradation of boron-containing styrenic polymers was studied by FTIR and boric acid was detected at high temperatures. LOI values increase with boron content.

Boron-containing novolac resins were synthesized by the modification of a commercial novolac resin with different contents of bis(benzo-1,3,2-dioxaborolanyl)oxide These novolac resins were crosslinked with diglycidyl ether of bisphenol A (DGEBA). and their thermal, thermodynamomechanical, and flame-retardant properties were evaluated. The boron-containing novolac resins were less thermally stable than the unmodified novolac resin. Their modification degree and DGEBA content were related to the crosslinking density of the materials. The boron-containing novolac resins generated boric acid at high temperatures and gave an intumescent char that slowed down the degradation and prevented it from being total. They also showed good flame-retardant properties.

The reactivity of sulfur-based epoxy monomers was studied by monitoring of a model system involving phenylglycidylthioether and aniline. The reaction was carried out under isothermal conditions and monitored in situ by near infrared spectroscopy. Using multivariate curve resolution-alternating least squares made it possible to obtain the concentration and spectral profiles of each species throughout the reaction. To obtain the kinetic rate constants, the values of the recovered concentration profiles were fitted to a kinetic model proposed for the reaction. Reactivity was evaluated by comparing the concentration profiles and kinetic rate constants obtained with the same parameters obtained for phenylglycidylether/aniline as a reference system. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4846–4856, 2006

A new phosphorous-containing fatty acid diepoxide was obtained from 10-undecenoyl chloride and 10-(2′,5′-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and crosslinked with 4,4′-diaminodiphenylmethane and bis(m-aminophenyl)methylphosphine oxide. The properties of the thermosetting materials were evaluated by differential scanning calorimetry, dynamic mechanical thermal analysis, thermogravimetric analysis, and limiting oxygen index (LOI). Thermal and thermooxidative degradation was studied by gas chromatography/mass spectrometry, FTIR, 31P magic angle spinning NMR spectroscopy, and scanning electron microscopy. LOI values indicate good flame-retardant properties that are related to the formation of a protective phosphorous-rich layer that slowed down the degradation and prevented it from being total. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5630–5644, 2006

Epoxy-novolac resins were synthesized by modifying a commercial novolac resin with epichlorohydrin. These epoxy-novolac resins were characterized and further modified with different contents of bis(benzo-1,3,2-dioxa-borolanyl)oxide or bis(4,4,5,5-tetramethyl-1,3,2-dioxa-borolanyl)oxide. The boron-containing epoxy-novolac resins were autocatalytically crosslinked or crosslinked with BF 3 MEA and their thermal stability and flame retardancy were determined by thermogravimetric analysis and limiting oxygen index (LOI) values. These LOI values for the bis(benzo-1,3,2-dioxa-borolanyl)oxide derivatives were higher than the boron-free novolac resins, which shows the benefit of the presence of boron. To test the role of boron in the enhancement of flammability, scanning electronic microscopy and energy-dispersive X-ray spectroscopy images were made.

Benzoxazines derived from aniline and 4-hydroxybenzoic acid and from phenol and 4-aminobenzoic acid were prepared with two different synthetic approaches. When the carboxylic group reacted with epichlorohydrin, glycidylic derivatives M-1 and M-2, respectively, were obtained. The ring opening of benzoxazine and epoxy took place simultaneously with no catalyst for both monomers. Likewise, both ring-opening polymerizations took place when boron trifluoride monoethylamine (BF3·MEA) or 4-(N,N-dimethylamino)pyridine was used as a catalyst for M-1. However, for M-2, when BF3·MEA was used as a catalyst, the epoxy and benzoxazine ring openings could be distinguished, and a polyether intermediate containing benzoxazine side chains could be obtained. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1529–1540, 2006

Novel hybrid organic-inorganic materials were prepared from 10-undecenoyl triglyceride and methyl 3,4,5-tris(10-undecenoyloxy)benzoate via hydrosilylation. 1,4-Bis(dimethylsilyl)benzene, tetrakis(dimethylsilyloxy)silane, and 2,4,6,8-tetramethylcyclotetrasiloxane were used as crosslinkers. The hydrosilylation reaction was catalyzed by Karstedt's catalyst [Pt(0)-divinyltetramethyldisiloxane complex]. The networks were structurally characterized by Fourier transform infrared spectroscopy, 13 C NMR, and 29 Si magic-angle-spinning NMR. The thermal properties of these hybrids were studied with differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical analysis. The obtained materials showed good transparency and promising properties for optical applications.

Oligomeric polyether polyols were obtained through the acid-catalyzed ring-opening polymerization of epoxidized methyl oleate and the subsequent partial reduction of ester groups to give primary alcohols. The oligomers were characterized with titration, spectroscopic techniques (Fourier transform infrared and nuclear magnetic resonance), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, size exclusion chromatography, and differential scanning calorimetry. Depending on the degree of reduction, polyols of different hydroxyl content values were obtained and were reacted with 4,4′-methylenebis(phenyl isocyanate) to yield polyurethanes. These materials, which were characterized by differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical thermal analysis, could behave as hard rubbers or rigid plastics. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 634–645, 2006

We investigated the dynamics and structure of the aliphatic side chains of a randomly grafted copolymer, obtained through the chemical modification of poly(epichlorohydrin) with potassium 3,4,5-tris(dodecyloxy)benzoate, with solid-state 13C NMR. Below 283 K, the aliphatic chains partially crystallized in an all-anti conformation. The calorimetric data were compatible with an orthorhombic packing. Below 323 K, the polymer exhibited a columnar mesophase. Spin–lattice relaxation times were determined in this temperature range and at 333 K, that is, in the isotropic phase. In the liquid-crystalline state, some carbons exhibited a double decay in the spin–lattice relaxation, and this was attributed to presence of the liquid-crystalline phase. This hypothesis was supported by a conformational analysis performed by molecular modeling. The activation energies of the relaxation processes in the mesophase were also estimated. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2099–2111, 2005

A set of high-molecular-weight new side-chain liquid-crystalline polyethers was obtained by chemical modification of poly(epichlorohydrin) with potassium 3,4,5-tris(dodecyloxy)benzoate. The degree of modification ranged from 48 to 70% depending on the reaction conditions, and the upper value was an apparent modification plateau. NMR characterization indicated that no side reactions of any kind occurred (e.g., deshydrohalogenation). All copolymers had a nematic columnar mesophase whose range of stability depended on the modification degree. X-ray diffraction experiments performed on mechanically oriented samples showed that tapered groups were tilted with respect to the column axes. Also X-ray experiments and density measurements demonstrated that the number of disks per unit cell decreased as the modification degree increased. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2918–2929, 2003

This is an extension of our previous work on mechanistic studies of the degradation of the main chain during the chemical modification of poly(oxy-1-chloromethylethylene) (PECH) with phenolate to similar studies on the modification of poly(oxy-1-chloromethylethylene-cooxyethylene) (PECH‐PEO) with the same reagent. This polymer has been chemically modified with phenolate in the presence of a quaternary ammonium salt, i.e. tetrabutylammonium bromide (TBAB). Several reaction conditions were tested to provide the highest modification degrees with the minimum main-chain cleavage. The substitution of chlorine by phenolate was found to be accompanied by elimination reactions that led to vinylether moieties. The 13 C NMR technique was used to identify the different terminal groups arising from this cleavage. The nature of these groups confirmed that cleavage was caused by nucleophilic attack on the units neighbouring vinylic ones, mainly on the VV dyads. The results are consistent with those obtained from the modification reaction of poly(oxy-1-chloromethylethylene) (PECH) with phenolate. q 2000 Elsevier Science Ltd. All rights reserved.

Poly(oxy-1-chloromethylethylene-co-oxyethylene) copolymer (PECH–PEO) has been modified chemically by phenolate, producing dehydrochlorination as a side reaction, because of its basic character. The comonomer composition of the resulting poly(oxy-1-chloromethylethylene-co-oxyethylene-co-oxy-1-methyleneethylene-co-oxy-1-phenoxy-methylethylene) can be quantitatively determined by 13C NMR spectroscopy. A series of copolymeric models were synthesized to make the complete assignment of all the signals appearing in the spectrum of the tetrapolymer. The various 13C NMR signals in the spectra were assigned to dyads, triads or tetrads of all the possible comonomer sequences and in some cases to the tacticity.

A series of oxiranic monomers was synthesized and polymerized by four of the most common aluminium-based coordinative initiators: (C 2 H 5 ) 3 Al/H 2 O (mole ratio 1:0.6) named Vandenberg catalyst, (C 2 H 5 ) 3 Al/CH 3 COCH 2 COCH 3 /H 2 O (mole ratio 1:1:0.5) named Vandenberg chelate catalyst, (i-PrO) 2 Al-O-Zn-O-Al(i-PrO) 2 named Teyssie catalyst and (i-PrO) 3 Al/ZnCl 2 (mole ratio 1:0.5) named Price catalyst. They all have a different Lewis acid character. The influence of a second oxygen (glycidylic or not) on the characteristics of the polymers and conversions was studied and rationalized on the basis of a coordinative mechanism. The differences in the polymerization rate and regioregularity of the polymers obtained are related to the electronic and coordination effects of the neighbouring oxirane substituents. The new polymers were also thermally characterized.

Poly(epichlorohydrin) [poly(oxy-1-chloro-methylethylene)] (PECH) has been modified chemically by basic nucleophiles, such as phenolate, producing dehydrochlorination as side reaction. The comonomer composition of the resulting poly(oxy-1-chloromethylethylene-co-oxy-1-phenoxymethyl-ethylene-co-oxy-1-methyleneethylene) can be determined by quantitative 13C nuclear magnetic resonance (n.m.r.) spectroscopy. Some polymeric models were synthesized in order to make accurate assignments, since most of the signals were not completely resolved. The various 13C n.m.r. signals were assigned to comonomer sequences in the main chain, which were fitted to a Bernouillian statistical model.

Starting from 4-methoxycarbonylphenyl glycidyl ether and unfunctionalized phenyl glycidyl ether, samples of highly regio- and stereoregular linear homo- and copolymers were synthesized using the ionic coordinative initiator system aluminium isopropoxide/ZnCl 2 . The polymers were first transformed into carboxylic acid derivatives and then into highly reactive carboxylic acid chlorides with high yields and conversions. The use of all these synthesized polymers was tested by transforming them into the corresponding 4-nitrobenzyl ester using different synthetic procedures. Finally, the scope of the methodology studied was tested by using it to synthesize a set of new polymers containing different complex groups such as: 18-crown-6, biphenyl-4-carbonitrile, anthraquinone, (1R)-nopol, (-)-inosine and 4-dodecylaniline, which are in general obtained with good yields and conversions.

The nucleophilic substitution reaction of poly(epichlorohydrin)(PECH) with phenolate has been studied. This process is accompanied by dehydrochlorination, which leads to a considerable proportion of vinyl ether moieties. The elimination side reaction seems to be responsible for the cleavage usually observed in this kind of modification process. Likewise, some attempts have been made in order to get high degrees of substitution by minimizing the cleavage. The chain scission has been mechanistically explained on the basis of the reactions of PECH homopolymer with phenolate and/or TBAB, of poly(oxy-1-methyleneethylene) with tetrabutyl ammonium bromide (TBAB) and poly(oxy-1-chloromethyl- ethylene-co-oxy-1-methyleneethylene) copolymer with phenolate and/or TBAB.

The growing demand for petroleum-based products and the resulting negative impact on the environment, plus the scarcity of nonrenewable resources, are some of the many factors that have recently raised the interest on the field of polymers derived from nonpetrochemical feedstock. Thus, increasing efforts have been focused on the use of plant oils and derivatives as monomers for polymer synthesis. However, like other organic polymeric materials, the flammability of these materials is a shortcoming in some applications and therefore the use of fire retardants to reduce its combustibility, along with smoke and toxic fume production, becomes a pivotal part of the development and application of these new biobased materials. In this context our approach goes further than the classical and already prohibited halogen based flame retardants, and deals with the incorporation of phosphorus, silicon or boron into different plant oil-derived polymeric structures.

As a complementary study of a previous work about the influence of the electronic effects of p-substituted phenyl glycidyl ethers on the polymerization behaviour, a new series of monomers with electron-withdrawing groups was prepared, i.e., highly reactive p-functionalized poly(phenyl glycidyl ethers) were prepared. The polymerizations were carried out with four different aluminium-based coordinative initiators, (C 2 H 5 ) 3 Al/H 2 O (mole ratio 1:0.6) (the Vandenberg catalyst), (C 2 H 5 ) 3 Al/CH 3 COCH 2 COCH 3 /H 2 O (mole ratio 1 :1 :0.5) (the Vandenberg chelate catalyst), [(CH 3 ) 2 CHO] 2 Al-O-Zn-O-Al[OCH(CH 3 ) 2 ] 2 (the Teyssie catalyst) and [(CH 3 ) 2 CHO] 3 Al/ZnCl 2 (the Price catalyst), all with different Lewis acid character. The influence of the electron withdrawing groups on the characteristics and conversion of polymers was studied. All polymers were characterized by nuclear magnetic resonance spectroscopy showing higher tacticities when the Price catalysts was used. In some cases the degree of conversion was low due to passivation effects which were studied in several experiments.

As a complementary study of a previous work about the influence of the electronic effects of p-substituted phenyl glycidyl ethers on the polymerization behaviour, a new series of monomers with electron-withdrawing groups was prepared, i.e., highly reactive p-functionalized poly(phenyl glycidyl ethers) were prepared. The polymerizations were carried out with four different aluminium-based coordinative initiators, (C2H5)3Al/H2O (mole ratio 1:0.6) (the Vandenberg catalyst), (C2H5)3Al/CH3COCH2COCH3/H2O (mole ratio 1:1:0.5) (the Vandenberg chelate catalyst), [(CH3)2CHO]2AlOZnOAl[OCH(CH3)2]2 (the Teyssie catalyst) and [(CH3)2CHO]3Al/ZnCl2 (the Price catalyst), all with different Lewis acid character. The influence of the electron withdrawing groups on the characteristics and conversion of polymers was studied. All polymers were characterized by nuclear magnetic resonance spectroscopy showing higher tacticities when the Price catalysts was used. In some cases the degree of conversion was low due to passivation effects which were studied in several experiments.

The reaction of carboxylic acid anhydride with poly(vinyl alcohol) (PVA) leads to vinyl alcohol—vinyl ester copolymers which contain carboxylic acid groups. Esterification enables degrees of modification to be reached which depend on the chemical structure of the anhydride introduced and the ratio of the reagents in the feed. The copolymers obtained were characterized by spectroscopic techniques, elemental analysis, and thermal methods. These half-esters reacted in a second step with aromatic diglycidyl ethers to obtain tridimensional networks. This crosslinking reaction through the carboxylic groups was studied by differential scanning calorimetry. The water absorption of the linear and crosslinked polymers was determined gravimetrically as a function of time at room temperature. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1643–1651, 1997