Copolymers Of Alkyl Methacrylates Research Articles

Energy transfer in luminescent complexes of EuIII and TbIII with homo- and copolymers of acrylic acid and alkyl methacrylates

The influence of the composition and structure of a macromolecular ligand on the efficiency of energy transfer in complexes of EuIII and TbIII with ligands based on acrylic acid has been studied. It has been found that a decrease in the size of an alkyl group of methacrylic esters and a low content of acrylic moieties of EuIII complexes with copolymers increase the efficiency of EuIII concentration quenching. Insertion of noncoordinative alkyl methacrylate into the polymeric chain results in an increase in the efficiency of energy transfer from Tb3+ to Eu3+.

Copolymers of higher alkyl methacrylates with triallyl cyanurate

AbstractCopolymers of higher methacrylates (propyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, and dodecyl) with triallyl cyanurate were synthesized by free‐radical polymerization using benzoyl peroxide as initiator. The properties of the copolymers such as thermal stability, Tg, Vicat softening temperature, hardness, refractive indices nD, chemical stability, density, and shrinkage on polymerization were studied. The influence of the alcohol alkyl chain length in methacrylates and the content triallyl cyanurate in copolymers on their properties is discussed. © 1995 John Wiley & Sons, Inc.

Association of Graft Copolymers of Alkyl Methacrylates with α-Methyl-ω-hydroxy-poly(oxyethylene) ethacrylates

Solution properties of the statistical copolymers of alkyl methacrylates (AMA) with α-methyl-ω-hydroxy-poly(oxyethylene) methacrylates (MPOEMA) (nonionic polysoaps) were studied using static and dynamic ligh scattering as a function of monomer composition and concentration in aqueous and methyl cellosolve solutions. The solubility of the copolymers in water was found to be dependent on molar contant of AMA. While copolymers with low content of hexyl methacrylate (HMA) (0 and 20 mole %) were directly soluble in water, forming true solutions with a low content of large swollen aggregates, copolymers with a higher content of HMA or lauryl methacrylate (LMA) were not directly dispersable in water. A special procedure, the stepwise dialysis from methyl cellosolve solutions against water, had to be used to prepare them in the pseudomicellar form. The copolymers were directly soluble in methyl cellosolve and its water solution containing up to 60 vol.% of water. Nevertheless, the light scattering experiments were dominated by light scattering of swollen particles of aggregated copolymer molecules. The copolymers were not soluble in the mixtures containing 70-100 vol.% of water. Paramaters of aggregates in the mixture with 60 vol.% of water and in pure water were found to be very similar.

Structure–property relationship in copolymers of methacrylic acid esters. I. Thermal behavior

AbstractThis article describes the synthesis and thermal characterization of copolymers of methyl methacrylate (MMA) and alkyl methacrylates. The copolymerization was carried out using different mol fractions (0.05–0.25) of alkyl methacrylates, i.e., octyl methacrylate (OMA)/decyl methacrylate (DMA)/lauryl methacrylate (LMA)/stearyl methacrylate (SMA), in the initial feed at 80°C. The copolymer composition was determined from 1H‐NMR. The thermal stability of the copolymers was investigated by thermogravimetric analysis and pyrolysis gas chromatography. A two/three‐step degradation was observed in the copolymer samples. The monomers were the major product of degradation in most of the copolymers except in SMA/MMA copolymers where the product of side‐group elimination was also observed. An attempt was also made to determine the yield of the monomers during degradation and then to evaluate the copolymer composition. © 1994 John Wiley & Sons, Inc.

Thermal decomposition of copolymers of methyl methacrylate and alkyl methacrylates obtained from a CSTR

Thermal decomposition of the copolymers of methyl methacrylate (MMA) with ethyl methacrylate (EMA) or n-butyl methacrylate (BMA) were investigated. The copolymers were obtained in a continuous stirred tank reactor (CSTR) using toluene and benzoyl peroxide, as solvent and initiator, respectively, at 80C. The volume was 1.2 litters and residence time was 3 hours. The thermal decomposition followed the second order kinetics for both MMA/EMA and MMA/BMA copolymers, which were almost in accordance with the order of copolymerization in a CSTR. The activation energies of thermal decomposition were in the ranges of 32-37 kcal/mol and 27-37 kcal/mole for MMA/EMA and MMA/BMA copolymers, respectively and a good additivity rule was observed against each composition for both copolymers. The thermogravimetric trace curve agreed well with the theoretical calculation.

Compatibilizing effects of copolymers of chloroprene and alkylmethacrylates with different alkyl groups in polychloroprene/poly(alkyl methacrylate) blends

Miscibility of blends of polychloroprene (CR) and poly(alkyl methacrylate)s (PAMAs), such as poly(ethyl methacrylate) (PEMA), poly(isobutyl methacrylate) (PiBMA) and poly(glycidyl methacrylate) (PGMA) prepared by casting from tetrahydrofuran, were investigated by their glass transition temperature behaviours and morphologies. Since the blends of CR and PAMA were incompatible regardless of the different alkyl groups, copolymers of chloroprene and ethyl methacrylate (poly(CP- co-EMA)), isobutyl methacrylate (poly(CP- co-iBMA)) and glycidyl methacrylate (poly(CP- co-GMA)) were prepared as compatibilizers by radical solution copolymerization. Compatibilization effects of those copolymers were studied for the CR/PAMA blends of 50 50 wt% composition. For comparison, the graft copolymers of alkyl methacrylates onto CR were also prepared. The copolymers and graft copolymers showed compatibilizing effects in the blends consisting of each homopolymer, and the copolymers showed better compatibilizing effect than the graft copolymers. It was concluded that the compatibilizing effect of the copolymers in the CR/PAMA blends was more prominent in the order poly(CP- co-GMA) > poly(CP- co-iBMA) > poly(CP- co-EMA).

Photodecomposition of Eu3+ complexes with macromolecular ligands based on acrylic acid

The spectroluminescent and photochemical properties of Eu3+ complexes with copolymers of acrylic acid and alkyl methacrylates were studied. It was found that the photochemical behavior of the macromolecular complexes differs significantly from that of the lowmolecular analogs: in the course of photodecomposition the luminescence intensity of Eu3+ noticeably increases rather than diminishes. The efficiency of the luminescence build up of Eu3+ depends on the composition and the structure of the initial macromolecular complexes. A low concentration of the metal, low content of acrylic acid, and increase in the length of the alkyl radical of methacrylate favor the enhancement of the efficiency of luminescence build up of the rare-earth ion.

Blends of poly(α-methylstyrene- stat-acrylonitrile) with poly(alkyl acrylate)s, poly(alkyl methacrylate)s, poly(di-alkyl itaconate)s and alkyl methacrylate copolymers

The miscibility behaviour of the copolymer poly(α-methylstyrene- stat-acrylonitrile) (MSAN) with poly(alkyl acrylate)s, poly(alkyl methacrylate)s and poly(dialkyl itaconate)s has been investigated, where the alkyl groups were methyl, ethyl, n-propyl and n-butyl. Only in the poly(alkyl methacrylate) series were miscible blends obtained; no miscible systems were found for mixtures of MSAN with the other two sets of polymers. “Miscibility windows” were established for the MSAN-poly(alkyl methacrylate) blends and lower critical solution temperatures were also measured. From a knowledge of the phase boundaries, segmental interaction energy density parameters ( B ij ) were calculated and used to make predictions about various copolymer-copolymer blends based on the appropriate monomers. These predictions were tested for blends of poly(α-methylstyrene- stat-acrylonitrile) and poly(methyl methacrylate- stat-acrylonitrile) and found to be very satisfactory.

Surface properties of copolymers of alkyl methacrylates with, methoxy (polyethylene oxide) metiiacrylates and their application as protein-resistant coatings

New polymeric surfactants, copolymers of alkyl methacrylates with methoxy (polyethylene oxide) methacrylates, were synthesized and characterized by gel permeation chromatography. They were studied as possible means to produce polyethylene oxide-rich surfaces by a simple coating treatment on common Hydrophobie medical materials. They were further studied as cleaners for the removal of proteins preadsorfaed on hydrophobic surfaces. The surface properties of the copolymers such as the adsorption properties of the copolymer on a hydrophobic surface, low density polyethylene, the protein-resistant character of the prepared polyethylene oxide surfaces and the effectiveness of the copolymers for removal of proteins pre-adsorbed on the surface, were investigated by X-ray photoelectron spectroscopy and by using 125l-labelled copolymers and 125l-labelled proteins. The surface properties of the synthesized copolymers were compared with those of commercially available polyethylene oxide containing block copolymer surfactants.

Thermal properties of copolymers of alkyl methacrylates with triallyl cyanurate

AbstractThe homo‐ and copolymers of triallyl cyanurate and methyl methacrylate, ethyl methacrylate, propyl methacrylate, n‐butyl methacrylate, and cyclohexyl methacrylate were synthesized by free radical bulk polymerization using benzoyl peroxide as the initiator. The thermal properties of the polymers have been studied. The influence of the triallyl cyanurate content on the thermal behaviour of the copolymers has been investigated.

A study of solutions of copolymers of higher alkyl methacrylates by flow birefringence and electron microscopy methods

Viscometry, flow birefringence, and electron microscope study of solutions of these copolymers with vinyl acetate show that solutions of these copolymers form solvates. The supermolecular formations thus arising have an ordered character in solutions of paraffin-naphthalene solvent only when the comonomers are copolymerized in this solvent.

Thermodynamics of statistical copolymers of N-vinylcarbazole and alkyl methacrylates

Heat capacity at atmospheric pressure (between 163 and 493 K) and specific volume (between 325 and 455 K and whithin the pressure interval of 15 to 210 MPa) have been measured for equimolar statistical copolymers of N-vinylcarbazole and a series of alkyl methacrylates (from methyl to lauryl). Parameters in the Simha-Somcynsky equation of state were determined for the copolymers in the liquid state, and the individual contributions to the discontinuity in heat capacity at the glass-transition temperature were calculated according to Di-Marzio. It has been demonstrated for the first time that the number of degrees of freedom of the repeat unit in the liquid state coincides with the number of “flexible” bonds contributing to internal rotation.

Synthesis, Structure, and Thermal Properties of Widely-Spaced Comb-Like Polymers

Alternating copolymers of butadiene and long alkyl methacrylates I and their hydrogenated copolymers II were synthesized, characterized and designated as widely-spaced comb-like polymers. A differential scanning calorimetry study of these copolymers indicated that their alkyl side chains could crystallize in the same order as those of poly (alkyl methacrylates).

Copolymers of 2-Hydroxyethyl Methacrylate and Alkyl Methacrylates. Part III. Thermal Behavior

Abstract The relative thermal stability of copolymers of 2-hydroxyethyl methacrylate-ethyl methacrylate (HEMA-EMA) and HEMA-n-butyl methacrylate (HEMA-BMA) was investigated by thermogravimetry in an air/nitrogen atmosphere. The effect of molecular weight on thermal degradation was evaluated by taking five fractions of HEMA-EMA and four of HEMA-BMA copolymers. The enthalpic changes associated with the endothermic transition were evaluated by differential scanning calorimetry. The structural changes taking place in these copolymers during thermal degradation in air at 200°C were investigated by IR.

Copolymers of alkyl methacrylates as pour-point depressants for diesel fuels

This paper reports on the synthesis by means of radical polymerization of homopolymers and copolymers of alkyl methacrylates with various lengths of the alkyl radical styrene and vinyl acetate, and evaluates their effectiveness as pour-point depressants for diesel fuels. It is established that when using such pourpoint depressants the limiting filterability temperature of diesel fuel is lowered by 5-10/sup 0/C and the solid point by 4-10/sup 0/C.

Thermal degradation of copolymers of 2-hydroxyethyl methacrylate and alkyl methacrylates

Thermal degradation of homopolymers of ethyl methacrylate ( I), n-butyl methacrylate ( II), 2-hydroxyethyl methacrylate ( III), and copolymers of III with I and II were carried out by thermal volatilization analysis (TVA) up to 440°C with subsequent subambient thermal volatilization analysis (SATVA). An on-line mass spectrometry coupled with TVA and SATVA was employed to identify the products of thermal degradations. Isothermal pyrolyses of the polymers were carried out separately at 400°C in vacuum for 30 min and the liquid products of decomposition were collected and analysed by gas chromatography. The relationship between the amounts of I and II obtained from pyrolysis and the amounts of these components actually present in the copolymer samples was determined. Also the amount of III and ethyleneglycol dimethacrylate obtained from pyrolysis increases with the amount of III in the copolymer. The polymers were also characterized by differential thermal analysis.

Glass transition of styrene/n‐alkyl methacrylate copolymers

AbstractDependences of the glass transition temperatures (Tg) of copolymers of styrene (ST) with the n‐alkyl methacrylates [methyl, ethyl, butyl and octyl methacrylate (MMA, EMA, BMA, and OMA)] on their overall chemical composition were measured. All the dependences investigated in this study satisfy the dyad approximation suggested earlier for the description of the sequential distribution effect on Tg of the copolymer either (1) using reciprocal Tg's and weight fractions of the dyads (according to Johnston), or (2) by means of Tg's and mole fractions of rotatable bonds corresponding to the respective dyads (according to Barton). It was shown that for copolymers the monomeric units of which did not differ too much in their number of rotatable bonds in the molecule (e.g., ST/MMA), both these approaches are satisfactory; if the comonomeric units differ markedly in the number of rotatable bonds (e.g., ST/OMA), approach (1) yields more realistic results than (2). Extrapolation to zero content of the styrene component in the copolymer ST/OMA gave Tg of poly(OMA) (245 K), which is experimentally inaccessible by the method employed (differential scanning calorimetry).

Copolymers of ethylene and alkyl methacrylates as pour depressants for diesel fuel

Copolymers of ethylene and alkyl methacrylates as pour depressants for diesel fuel

Study of oil soluble polymers as drag reducers

AbstractThis investigation was undertaken to find the most effective material which would reduce the friction coefficient in turbulent flow when added in small quantities to oil pipelines. For this purpose, a series of oil‐soluble polymers, namely homopolymers and copolymers of alkyl methacrylates, alkyl acrylates, and alkyl styrenes were synthesized. Emulsion polymerization techniques were used. Commercially available alkyl methacrylate and alkyl acrylate monomers were used in the synthesis. Monomeric alkyl styrenes were synthesized and structures established prior to polymerization. Intrinsic viscosities were measured and viscosity average molecular weights were calculated for several of the homopolymers synthesized in this study. Reduction of factional drag and resistance to shear degradation were measured by pumping a solution of the polymer in a hydrocarbon solvent through a pipe and recording the pressure drop across the pipe. Drag‐reducing properties of several of the polymers were correlated in terms of their viscosity average molecular weights. Drag reduction of poly (isodecyl methacrylate) was studied in various hydrocarbon solvents. Drag‐reducing behavior of polymers prepared in this study exhibited a strong dependence on molecular weight; increasing the molecular weight increased the drag reduction for a given polymer concentration and pipe size. Several of these polymers were found to be superior to commercially available polyisobutylene as drag reducers, especially in terms of shear stability.

Thermal analysis of styrene–alkyl methacrylate polymers. I. Glass transition temperatures

AbstractThe glass transition temperatures (Tg's) of several polystyrenes and styrene–alkyl methacrylate copolymers and terpolymers were measured using thermomechanical analysis (TMA) and differential scanning calorimetry (DSC). The polymers studied had number‐average molecular weights from 3000 to 250,000 g/mole. The results indicate that the composition dependence of the Tg's for the copolymers and terpolymers can be satisfactorily described by a general Fox equation. In general, the measured Tg's of the copolymer and terpolymer samples depend more on the steric effects of the constituent pendent groups than on their molecular weights. The chain flexibility rather than the size of the pendent group is the determining factor in the glass transition properties of the styrene polymers.