Free radical copolymerization kinetics of γ-methyl-α-methylene-γ-butyrolactone (MeMBL).

The propagation kinetics and copolymerization behavior of the biorenewable monomer γ-methyl-α-methylene-γ-butyrolactone (MeMBL) are studied using the pulsed laser polymerization (PLP)/size exclusion chromatography (SEC) technique. The propagation rate coefficient for MeMBL is 15% higher than that of its structural analogue, methyl methacrylate (MMA), with a similar activation energy of 21.8 kJ·mol(-1). When compared to MMA, MeMBL is preferentially incorporated into copolymers when reacted with styrene (ST), MMA, and n-butyl acrylate (BA); the monomer reactivity ratios fit from bulk MeMBL/ST, MeMBL/MMA, and MeMBL/BA copolymerizations are r(MeMBL) = 0.80 ± 0.04 and r(ST) = 0.34 ± 0.04, r(MeMBL) = 3.0 ± 0.3 and r(MMA) = 0.33 ± 0.01, and r(MeMBL) = 7.0 ± 2.0 and r(BA) = 0.16 ± 0.03, respectively. In all cases, no significant variation with temperature was found between 50 and 90 °C. The implicit penultimate unit effect (IPUE) model was found to adequately fit the composition-averaged copolymerization propagation rate coefficient, k(p,cop), for the three systems.

Training peer specialists with mental illness in motivational interviewing: A pilot study.

OBJECTIVE: The objective of this study was to evaluate the effects of providing motivational interviewing (MI) training to peer specialists in the Veterans Affairs (VA) health-care system. METHODS: Fourteen peer specialists at a local VA medical center received a 2-day workshop on MI and 2 monthly booster sessions afterward. A total of 55 therapy sessions between peer specialists and their peer service recipients were audio-recorded and independently rated on MI fidelity before the workshop and each month after the workshop for 3 months. Sessions were rated on fidelity scales assessing Fundamental MI Adherence and Competence, Advanced MI Adherence and Competence, and MI Inconsistent Adherence scales. One item was created for this study that assessed Sharing Lived Experiences. Repeated measures analysis was conducted to examine change in MI fidelity over time. RESULTS: Peer specialists had a significant decline in MI Inconsistent Adherence scale scores over time. Specifically, they showed reductions in providing unsolicited advice and emphasizing absolute abstinence. Peer specialists also showed a significant decline in the Sharing Lived Experience Adherence item score. There were no significant changes on MI Fundamental and Advance scale scores. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Training peer specialists in MI is feasible and may lead to some change in practices, but comprehensive training and ongoing supervision is needed to incur and sustain changes. Guidance and assessment of how peer specialists share their lived experiences with fellow veterans may be needed to capitalize on their unique experiences and skill sets. (PsycINFO Database Record

Nitroxide-Mediated Polymerization at Elevated Temperatures.

A new alkoxyamine based on a highly thermally stable nitroxide is used for the controlled polymerization of styrene and butyl acrylate at temperatures up to 200 °C. High monomer conversions are reached in a few minutes with a linear increase in polymer chain-length with conversion, a final dispersity (D) of ∼1.2, and successful chain-extension of the resulting material. The alkoxyamine concentration was altered to target various chain lengths, with autopolymerization dictating the polymerization rate of styrene regardless of alkoxyamine concentration. Controlled polymerization of methacrylate monomers and acrylic acid was successful with the addition of styrene. The new material opens the possibility to increase the range of specialty products made for applications in coatings, inks, overprint varnishes, and adhesives.