Proton NMR Measurements Research Articles

Synthesis, structural characterization and nematicidal studies of some new N2O2 Schiff base metal complexes

ABSTRACT. Cobalt(II), copper(II), yttrium(III), zirconium(IV), lanthanum(III) and uranium(VI) complexes of 1,4-di(2-hydroxybenzylidene)thiosemicarbazide (H2L) were prepared and characterized. The proposed structures were determined from their elemental analyses, molar conductivities, magnetic moment, IR, Proton NMR, UV-Vis., mass spectra, X-ray diffraction and thermal analyses measurements. The high conductance data supply evidence for the electrolytic nature of the complexes. The changes in the selected bands in IR of Schiff base ligand upon coordination showed that Schiff base exhibits as a neutral tetradentate manner with oxygen and nitrogen donor sites. The complexes are thermally steady at room temperature and break up to two or three steps. The kinetic and thermodynamic parameters of complexes have been determined by using Coats-Redfern and Horowitz-Metzeger methods at n=1 and n≠1 and values suggest more ordered activated complex formation. The calculated bond length and force constant, F(U=O), in the uranyl complex are 1.744 Å and 664.886 Nm-1. The nematicidal activity of free Schiff base and all complexes were investigated and showed a low inhibition percentage (%I) of complexes compared with H2L.
 
 KEY WORDS: Schiff base, IR, Thermal, XRD, Nematicidal activity
 
 Bull. Chem. Soc. Ethiop. 2021, 35(2), 315-335.
 DOI: https://dx.doi.org/10.4314/bcse.v35i2.8

Multi-component relaxation modelling in human Achilles tendon: Quantifying chemical shift information in ultra-short echo time imaging.

To examine multi-component relaxation modelling for quantification of on- and off-resonance relaxation signals in multi-echo ultra-short echo time (UTE) data of human Achilles tendon (AT) and compare bias and dispersion errors of model parameters to that of the bi-component model. Multi-component modelling is demonstrated for quantitative multi-echo UTE analysis of AT and supported using a novel method for determining number of MR-visible off-resonance components, UTE data from six healthy volunteers, and analysis of proton NMR measurements from ex vivo bovine AT. Cramer-Rao lower bound expressions are presented for multi- and bi-component models and parameter estimate variances are compared. Bias error in bi-component estimates is characterized numerically. Two off-resonance components were consistently detected in all six volunteers and in bovine AT data. Multi-component model exhibited superior quality of fit, with a marginal increase in estimate variance, when compared to the bi-component model. Bi-component estimates exhibited notable bias particularly in in the presence of off-resonance components. Multi-component modelling more reliably quantifies tendon matrix water components while also providing quantitation of additional non-water matrix constituents. Further work is needed to interpret the origin of the observed off-resonance signals with preliminary assignments made to chemical groups in lipids and proteoglycans.

Thermoporometry and Proton NMR Measurement on Cement Paste Equilibrated at Different Relative Humidities

Thermoporometry and Proton NMR Measurement on Cement Paste Equilibrated at Different Relative Humidities

Fluorometric sensing of hydroxylamine in an aqueous medium utilizing a diphenyl imidazole-based probe.

The detection of hydroxylamine in an aqueous medium is challenging due to its very similar chemical reactivity to its nearest competitors such as hydrazine hydrate and primary amines. Moreover, the detection of hydroxylamine at neutral pH adds further complexity to the sensing phenomenon due to its poor reactivity in a neutral aqueous medium. In this work, we have presented a diphenyl imidazole benzaldehyde (DIB) probe which demonstrates the detection of hydroxylamine (HA) in micromolar concentrations with high selectivity in 5% DMSO phosphate buffer solution at pH 7.4 via a fluorescence "turn-on" signal. The interaction of hydroxylamine with the probe has been comprehensively studied by using fluorescence spectroscopy, proton NMR, FTIR, ESI-mass spectrometry and DLS measurements. The experimental results were further corroborated with the DFT studies. These results could pave the way toward the development of molecular indicators for hydroxylamine in chemical and biological platforms.

Gramicidin Increases Lipid Flip-Flop in Symmetric and Asymmetric Lipid Vesicles

Unlike most transmembrane proteins, phospholipids can migrate from one leaflet of the membrane to the other. Because this spontaneous lipid translocation (flip-flop) tends to be very slow, cells facilitate the process with enzymes that catalyze the transmembrane movement and thereby regulate the transbilayer lipid distribution. Nonenzymatic membrane-spanning proteins with unrelated primary functions have also been found to accelerate lipid flip-flop in a nonspecific manner and by various hypothesized mechanisms. Using deuterated phospholipids, we examined the acceleration of flip-flop by gramicidin channels, which have well-defined structures and known functions, features that make them ideal candidates for probing the protein-membrane interactions underlying lipid flip-flop. To study compositionally and isotopically asymmetric proteoliposomes containing gramicidin, we expanded a recently developed protocol for the preparation and characterization of lipid-only asymmetric vesicles. Channel incorporation, conformation, and function were examined with small angle x-ray scattering, circular dichroism, and a stopped-flow spectrofluorometric assay, respectively. As a measure of lipid scrambling, we used differential scanning calorimetry to monitor the effect of gramicidin on the melting transition temperatures of the two bilayer leaflets. The two calorimetric peaks of the individual leaflets merged into a single peak over time, suggestive of scrambling, and the effect of the channel on the transbilayer lipid distribution in both symmetric 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine and asymmetric 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine/1,2-dimyristoyl-sn-glycero-3-phosphocholine vesicles was quantified from proton NMR measurements. Our results show that gramicidin increases lipid flip-flop in a complex, concentration-dependent manner. To determine the molecular mechanism of the process, we used molecular dynamics simulations and further computational analysis of the trajectories to estimate the extent of membrane deformation. Together, the experimental and computational approaches were found to constitute an effective means for studying the effects of transmembrane proteins on lipid distribution in both symmetric and asymmetric model membranes.

Analysis of Second-Order Pattern of Proton NMR Spectrum of 1,3-Dichloro-2-nitrobenzene

Abstract The analysis of a second-order pattern on a proton NMR spectrum is proposed using a multi field NMR measurement, a spectral simulation, a DFT calculation and a solvent effect study. The ordinary 9.4 T proton NMR measurement of 1,3-dichloro-2-nitrobenzene in organic solvents gave the AB2 spectrum showing the second-order pattern. The higher field, 14.1 T proton NMR measurement gave the spectrum close to the AX2 showing the first-order pattern with a little roofing. Then the peak assignments were confirmed by the spectral simulation using the NMR parameters obtained from each experimental spectra. Finally, the NMR parameters are discussed from the results of the DFT calculation and the solvent effect study.

Towards a NMR-Based Method for Characterizing the Degradation of Nafion XL Membranes for PEMFC

PFSA-based reinforced membranes are used today as the benchmark material for the electrolyte in PEMFCs. Although greatly improved relatively to their unreinforced version, they still suffer from aging and degradation during fuel cell (FC) operation. In this study we first performed proton NMR to characterize the different water populations in the pristine Nafion XL reinforced membrane. Then we used proton and fluorine NMR, FTIR and sorption measurements in order to qualitatively observe the differences induced in the membrane's chemical structure and properties by long term FC operation. Proton NMR is seen to be an adapted tool to quickly measure a signature that is correlated to the degradation state while FTIR can serve as a local probe of the chemical structure.

Ionic liquid-based dye: A “Dyed plasticizer” for rapid and highly sensitive anion optodes based on a plasticized PVC membrane

Abstract An ionic liquid-based dye was synthesized and directly used as a plasticizer in a plasticized poly(vinyl chloride) (PVC) membrane-based anion optode. In contrast to conventional PVC-based optode membranes, the optode membrane presented can contain a very high concentration (∼296.1 mmol/kg) of dye molecules (for conventional membranes, the concentration is typically 5–50 mmol/kg), which allowed the preparation of a very thin membrane (∼0.8 μm) exhibiting a rapid response time (6.5 s), with sufficient sensitivity (1.2 Absorbance unit (AU)) and excellent response reversibility. We prepared the ionic liquid-based dye using trihexyltetradecylphosphonium (P66614) as a lipophilic monocation and naphtholphthalein (NP) as a dianion. The prepared ionic liquid-based dye contained approximately 40% dye relative to the formula [P66614]2[NP], as confirmed by proton NMR measurements and elemental analysis. Optimized PVC content of the plasticized PVC membrane, without leaching of dye, was 10 wt%. Under these conditions, surprisingly, the membrane exhibited fully reversible responses to acidic and basic solutions, even though the dye was not lipophilized using long alkyl chains, something that has been considered an indispensable chemical modification for dyes used in typical ion-selective optodes. A comparison with conventional plasticized PVC membranes, using nitrophenyl octyl ether (NPOE) as a typical plasticizer and a lipophilic derivative of NP as a lipophilic dye, was carried out in terms of the response time and sensitivity, the results of which demonstrated the advantages of the present approach. Finally, as the simplest application, a plasticized PVC membrane based on an ionic liquid-based dye was successfully applied to coextraction-based anion sensing.

Ultrahigh-Resolution NMR Spectroscopy for Rapid Chemical and Biological Applications in Inhomogeneous Magnetic Fields.

NMR spectroscopy is a commonly used analytical technique in practical applications, and its applicability is further promoted by pure chemical shift techniques based on spectral simplification for analyses. Unfortunately, magnetic field inhomogeneity caused by adverse experimental conditions remains an obstacle restricting NMR applications. In this study, we introduce a new NMR method for high-resolution pure shift proton (1H) NMR measurements in inhomogeneous magnetic fields. We demonstrate that the method allows one to perform chemical analyses on complex solutions in deshimmed magnetic fields, to obtain metabolite information on intact biological tissues with intrinsic field inhomogeneities and to achieve in situ electrochemical detection under externally adverse field conditions. This approach is readily implemented on common commercial NMR instruments without field shimming and locking procedures, specialized hardware requirements as well as complicated sample pretreatments. It provides an effective tool for NMR applications to high-resolution chemical and biological measurements under inhomogeneous magnetic field conditions.

The Metabolic Syndrome in Men study: a resource for studies of metabolic and cardiovascular diseases

The Metabolic Syndrome in Men (METSIM) study is a population-based study including 10,197 Finnish men examined in 2005-2010. The aim of the study is to investigate nongenetic and genetic factors associated with the risk of T2D and CVD, and with cardiovascular risk factors. The protocol includes a detailed phenotyping of the participants, an oral glucose tolerance test, fasting laboratory measurements including proton NMR measurements, mass spectometry metabolomics, adipose tissue biopsies from 1,400 participants, and a stool sample. In our ongoing follow-up study, we have, to date, reexamined 6,496 participants. Extensive genotyping and exome sequencing have been performed for essentially all METSIM participants, and >2,000 METSIM participants have been whole-genome sequenced. We have identified several nongenetic markers associated with the development of diabetes and cardiovascular events, and participated in several genetic association studies to identify gene variants associated with diabetes, hyperglycemia, and cardiovascular risk factors. The generation of a phenotype and genotype resource in the METSIM study allows us to proceed toward a "systems genetics" approach, which includes statistical methods to quantitate and integrate intermediate phenotypes, such as transcript, protein, or metabolite levels, to provide a global view of the molecular architecture of complex traits.

Nuclear Spin Singlet Order Selection by Adiabatically Ramped RF Fields.

We describe an NMR method to generate singlet order in spin pairs from longitudinal spin magnetization and suppress residual background signals. This method can also be used for generating and observing long-lived spin states. A singlet order selection (SOS) filter is proposed, which allows us to find signals of the spin pair of interest buried in a crowded NMR spectrum. Likewise, SOS filtering enables proton NMR measurements in H2O without pulse sequences for solvent suppression. We demonstrate that the method works perfectly for both weakly and strongly coupled spin pairs. Furthermore, it can be combined with standard NMR pulse sequences: in this way, T1- and T2-relaxation times for spin pairs of interest can be measured. The power of the SOS-filter is demonstrated by relaxation studies in biomolecules.

Unfolding Kinetics of Human Telomeric G-Quadruplexes Studied by NMR Spectroscopy

Characterization of the unfolding kinetics of G-quadruplexes (G4s) is the key to a better understanding of the biological function of G4s and is important for biomedical research and material design. Of interest is that slight variations of human telomeric sequences can form different types of G4 structures. In general, there is a correlation between unfolding kinetics and thermal stability. Here we examined this correlation by first systematic analysis of the unfolding kinetics of a variety of telomeric G4 structures using the real-time imino proton NMR spectra of DNA hybridization and hydrogen-deuterium exchange (HDX). We then measured the melting temperature (Tm) and determined the Gibbs free energy (ΔG) of these G4 structures using differential scanning calorimetry (DSC). Our results showed that both Tm and ΔG are slightly structure-dependent, except the Tm of the parallel G4 structure is ∼10 °C higher than that of nonparallel G4 structures. The hybridization results showed that the decay times of different imino proton signals for each telomeric G4 structure are quite similar, which are also consistent with the time constant of the central G-tetrad obtained from HDX measurements. It is suggested that global unfolding is the rate-determining step for HDX, and each real-time imino proton NMR measurement can provide the intrinsic unfolding rate constant. The key finding is that the unfolding times of these various G4 structures are quite different and show no correlation between thermal stability and unfolding kinetics. Our results raised an issue that the folding and unfolding kinetics is more relevant for better understanding of biological function of G4 structures.

Chemical Characterization of Gilsonite Bitumen

This research provides new insights into the chemical composition of the Gilsonite in order to ascertain its properties which can assist in the refining and processing paths of the natural resource. Gilsonite, naturally occurring asphaltite bitumen, consists of a complex mixture of organic compounds. It was collected in the Uinta Basin near the town of Bonanza, Utah. The aim of this work is to obtain a more complete picture of molecular structure of Gilsonite, very important in fuel processing industry, matching and interpreting the results from different techniques. The Gilsonite was characterized by elemental analysis (EA) to determine the concentrations of C, H, N, S, and O, by Fourier transform infrared spectroscopy (FTIR) for comparative analysis of the chemical structures, by Nuclear magnetic resonance spectroscopy of hydrogen (1H NMR) to ascertain the aliphatic and aromatic hydrogen fractions, and by Thin layer chromatography-flame ionization detection (Iatroscan TLC-FID) to quantify saturated and aromatic hydrocarbons, and resin/asphaltene fractions. The results were evaluated in combination with the available geological data and with some bitumens to evaluate, chemically, possible mechanisms of Gilsonite formation. Low hydrogen to carbon atomic ratio (1.44), low sulfur (0.27 wt.%) and high nitrogen (3.25 wt.%) contents were the main characteristics of the Gilsonite from Uinta Basin. FTIR revealed the presence of alkane, aromatic rings, phenyl rings, alcohols, carbonyl groups, organic sulfoxides, and sulfate salts, confirming the fact that Gilsonite is composed of high molecular weight polycyclic constituents comprising of nitrogen, sulfur and oxygen heteroatoms. Likewise, FTIR proved that Gilsonite includes fingerprint of clay minerals. Iatroscan data showed interestingly that Gilsonite contains considerable amount of asphaltenes (79.7 wt.%) and nil amount of aromatics (0 wt.%). While, the yields of saturates and resins account only for 1.6 wt.% and 18.7 wt.%, respectively. Furthermore, SARA method estimated that Gilsonite is extremely instable (Colloidal instability index, CII = 4.34). Proton NMR measurements indicated that the aliphatic hydrogen portion is approximately 95.38% and the aromatic hydrogen fraction is about 4.62%.

Photophysical investigations on supramolecular fullerene/phthalocyanine charge transfer interactions in solution

The photophysical features of non-covalently linked fullerenes C60 and C70 with a designed free-base phthalocyanine, namely, 2,3,9,10,16,17,23,24-octakis-(octyloxy)-29H,31H-phthalocyanine (1) have been investigated employing various spectroscopic tools like UV–vis absorption spectrophotometry, steady state and time resolved fluorescence along with proton NMR measurements in toluene. The ground state interaction between fullerenes and 1 is nicely demonstrated with the appearance of well defined charge transfer absorption bands in the visible region of the electronic spectra. Steady state fluorescence experiment reveals efficient quenching of the excited singlet state of 1 in presence of both C60 and C70. The average values of binding constants for the non-covalent complexes of C60 and C70 with 1 are determined to be ∼18,150 and ∼32,000dm3mol−1, respectively. The magnitude of K suggests that 1 preferentially binds C70 in comparison to C60 although average value of selectivity in binding is measured to be low (∼1.75). Time resolved emission measurements establish photoinduced energy transfer from the excited singlet state of 1 to fullerene in toluene. Measurements of free energy of electron transfer and free energy of radical ion-pair formation elicit that C70/1 complex is stabilized more in comparison to C60/1 complex regarding generation of charge-separated state. Proton NMR studies provide very good support in favor of effective ground state complexation between fullerenes and 1. Semi empirical theoretical calculations on fullerene/1 systems in vacuo substantiate the stronger binding between C70 and 1 in comparison to C60/1 system in terms of heat of formation value of the respective complexes, and determine the orientation of bound guest (here C70) towards the plane of 1 during complexation.

Catalytic mechanism of human UDP-glucose 6-dehydrogenase: in situ proton NMR studies reveal that the C-5 hydrogen of UDP-glucose is not exchanged with bulk water during the enzymatic reaction

Human UDP-glucose 6-dehydrogenase (hUGDH) catalyzes the biosynthetic oxidation of UDP-glucose into UDP-glucuronic acid. The catalytic reaction proceeds in two NAD+-dependent steps via covalent thiohemiacetal and thioester enzyme intermediates. Formation of the thiohemiacetal adduct occurs through attack of Cys276 on C-6 of the UDP-gluco-hexodialdose produced in the first oxidation step. Because previous studies of the related enzyme from bovine liver had suggested loss of the C-5 hydrogen from UDP-gluco-hexodialdose due to keto-enol tautomerism, we examined incorporation of solvent deuterium into product(s) of UDP-glucose oxidation by hUGDH. We used wild-type enzyme and a slow-reacting Glu161→Gln mutant that accumulates the thioester adduct at steady state. In situ proton NMR measurements showed that UDP-glucuronic acid was the sole detectable product of both enzymatic transformations. The product contained no deuterium at C-5 within the detection limit (⩽2%). The results are consistent with the proposed mechanistic idea for hUGDH that incipient UDP-gluco-hexodialdose is immediately trapped by thiohemiacetal adduct formation.

Porewater in Compacted Water-Saturated MX-80 Bentonite

ABSTRACTBentonite is planned to be used in many countries as a buffer material in repositories for spent nuclear fuel. The proper understanding and modelling of the functioning of the water-saturated bentonite requires knowledge about the bentonite microstructure and also the way water is distributed between different phases. This paper presents experimental results from our studies of water in compacted, water-saturated MX-80 bentonite at dry densities in the range 0.7-1.6 g/cm3. Three techniques, Cl-porosity, SAXS and proton NMR measurements, were applied to samples kept at room temperature, while TEM imaging was applied to high pressure frozen samples. The combined results of these techniques strongly indicate that the two major water phases in the compacted MX-80 bentonite samples are ‘interlayer’ and ‘non-interlayer’ water. The results of the relative amounts of different water types by SAXS and NMR are very similar. The results by Cl-porosity measurement indicate that only part of the non-interlayer water is available for anions. Those observations are discussed in comparison to TEM micrographs. Our study provides solid experimental evidence for the presence of two major water phases in water-saturated bentonite and estimates their relative proportions and pore sizes.

Excited state relaxation dynamics of model green fluorescent protein chromophore analogs: evidence for cis-trans isomerism.

Two green fluorescent protein (GFP) chromophore analogs (4Z)-4-(N,N-dimethylaminobenzylidene)-1-methyl-2-phenyl-1,4-dihydro-5H-imidazolin-5-one (DMPI) and (4Z)-4-(N,N-diphenylaminobenzylidene)-1-methyl-2-phenyl-1,4-dihydro-5H-imidazolin-5-one (DPMPI) were investigated using femtosecond fluorescence up-conversion spectroscopy and quantum chemical calculations with the results being substantiated by HPLC and NMR measurements. The femtosecond fluorescence transients are found to be biexponential in nature and the time constants exhibit a significant dependence on solvent viscosity and polarity. A multicoordinate relaxation mechanism is proposed for the excited state relaxation behavior of the model GFP analogs. The first time component (τ(1)) was assigned to the formation of twisted intramolecular charge transfer (TICT) state along the rotational coordinate of N-substituted amine group. Time resolved intensity normalized and area normalized emission spectra (TRES and TRANES) were constructed to authenticate the occurrence of TICT state in subpicosecond time scale. Another picosecond time component (τ(2)) was attributed to internal conversion via large amplitude motion along the exomethylenic double bond which has been enunciated by quantum chemical calculations. Quantum chemical calculation also forbids the involvement of hula-twist because of high activation barrier of twisting. HPLC profiles and proton-NMR measurements of the irradiated analogs confirm the presence of Z and E isomers, whose possibility of formation can be accomplished only by the rotation along the exomethylenic double bond. The present observations can be extended to p-HBDI in order to understand the role of protein scaffold in reducing the nonradiative pathways, leading to highly luminescent nature of GFP.

Zinc selective chemosensor based on pyridyl-amide fluorescence

Chemosensors are developed to image zinc ions. Fluorescence enhancement due to Zn 2+ binding is an excellent way to detect its presence. A chemosensor for Zn 2+ based on dipicolylamine (DPA) groups connected by a pyridyl amide backbone has been synthesized. Addition of 2-chloroacetyl chloride to 2,6-diaminopyridine affords 2,6-bis(chloroethylamido)pyridine, which is converted to the sensor BADPA- P by 2,2′-dipicolylamine displacement of chlorine. This compound along with two others, the mono-DPA, ADPA- P and the benzyl in place of pyridyl, BADPA- B, present three potential Zn 2+ sensors. It was found that BADPA- P in the presence of Zn 2+ shows a large increase in fluorescence, whether in polar organic or aqueous environments. Its fluorescence in the presence of Cd 2+, unlike with Zn 2+, is not enhanced when excited at longer wavelengths. Proton NMR measurements, indicate two Zn 2+ ions bind to BADPA- P. Also, Zn 2+ enhances fluorescence even when other metal ions are present.

ChemInform Abstract: Cope Rearrangement and Molecular Reorientation in Solid Bullvalene: A Single Crystal Deuterium NMR Study.

Deuterium NMR spectra of single crystals of deuterated bullvalene were recorded in the temperature range -13 0C to +80 0 C. The measurements were performed with the magnetic field parallel to the crystallographic 6-axis where all four molecules in the unit cell are magnetically equivalent. Below about 5 0C the spectrum consists of ten almost symmetrical doublets due to the ten distinct deuterons per bullvalene molecule. Above 5 0C dynamic line broadening effects set in which were quantitatively interpreted in terms of two independent thermally activated processes: (i) symmetric 3-fold jumps about the molecular C3 axis and (ii) Cope rearrangement combined with molecular reorientation that preserves the crystal symmetry. The kinetic equations for the rates of the 3-fold jumps and the Cope rearrangement processes are respectively, k3 = 13.6 X 10 exp(-19.1//?r> and £c = 4.02 X 1014 exp(~\5.\/RT), where R is in kcal/mol-deg and the k's are in s1. Deuterium NMR measurements on a powder sample of deuterated bullvalene were also performed and found consistent with those obtained from the single crystals. The results are discussed in comparison with earlier solid state proton and 13C NMR and structural crystallographic measurements. We also show that the bullvalene molecules undergo an inde­ pendent 3-fold jump process, and we determine the rate of this process as well. It thus turns out that solid bullvalene is at the same time a highly order crystalline system and also highly fluxional. It exhibits, both whole-molecule jumps and valence-bond tautomerism but using pathways that leave the site symmetry in the crystal completely unchanged. The experimental details including the mounting and NMR measurements of the bullvalene single crystals are described in the Experimental Section. The single crystal measurements at low temperatures and in the temperature range where dynamic effects are observed, are then presented and compared with theoretically calculated lineshapes from which kinetic parameters are derived. These parameters are subsequently used to simulate and analyze the spectra obtained from a powder sample of bullvalene. We close with a short summary and conclusions which

An Investigation of Free Radical Copolymerization Kinetics of the Bio‐renewable Monomer γ‐Methyl‐α‐methylene‐γ‐butyrolactone with Methyl methacrylate and Styrene

AbstractThe free‐radical copolymerization propagation kinetics of the bio‐renewable monomer γ‐methyl‐α‐methylene‐γ‐butyrolactone (MeMBL) with styrene (ST) and with methyl methacrylate (MMA) have been investigated by the pulsed laser polymerization (PLP)—size exclusion chromatography (SEC) technique, in addition to DSC and proton NMR measurements. Monomer reactivity ratios for bulk MeMBL/ST and MeMBL/MMA copolymerizations are rMeMBL = 0.80 ± 0.04 and rST = 0.34 ± 0.04 and rMeMBL = 3.0 ± 0.3 and rMMA = 0.33 ± 0.01, respectively, with no significant variation with temperature found between 22 and 90 °C. The implicit penultimate unit effect (IPUE) model best represents the composition‐averaged copolymerization propagation rate coefficient, kp,cop for the MeMBL/ST system. Arrhenius parameters were estimated for MeMBL homopolymerization and found to be quite similar to those of MMA. DSC results show that copolymers of well controlled composition can be produced to suit specific Tg requirements over a much higher temperature range than possible with current acrylic glasses.magnified image