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A new monomer acetylated acrylic isosorbide (AAI) was prepared in two steps using common reagents without the need for column chromatography. Free radical polymerization of AAI afforded poly­(acetylated acrylic isosorbide) (PAAI), which exhibited a glass transition temperature (T g) = 95 °C and good thermal stability (T d, 5% weight loss; N2 = 331 °C, air = 291 °C). A series of ABA triblock copolymers with either poly­(n-butyl acrylate) (PnBA) or poly­(2-ethylhexyl acrylate) (PEHA) as the low T g midblocks and PAAI as the high T g end blocks were prepared using Reversible Addition–Fragmentation chain Transfer (RAFT) polymerization. The triblock copolymers ranging from 8–24 wt % PAAI were evaluated as pressure sensitive adhesives by 180° peel, loop tack, and static shear testing. While the PAAI-PEHA-PAAI series exhibited poor adhesive qualities, the PAAI-PnBA-PAAI series of triblock copolymers demonstrated peel forces up to 2.9 N cm–1, tack forces up to 3.2 N cm–1, and no shear failure up to 10 000 min. Dynamic mechanical analysis indicated that PAAI-PEHA-PAAI lacked the dissipative qualities needed to form an adhesive bond with the substrate, while the PAAI-PnBA-PAAI series exhibited a dynamic mechanical response consistent with related high performing PSAs.

A new monomer, acetylated methacrylic isosorbide (AMI), was synthesized in two steps employing scandium­(III) triflate as a remarkably efficacious catalyst for the tandem esterification of isosorbide with acetic anhydride and methacrylic anhydride. Analysis of the crude product mixture after acetylation indicated that functionalization occurred preferentially at the endo hydroxyl group of isosorbide (endo-acetate:exo-acetate = 4.2:1). Reaction of this mixture with methacrylic anhydride gave the corresponding isomeric mixture of AMI monomers. Poly­(AMI) [PAMI] prepared by radical polymerization of the mixture of AMI regioisomers was found to have a high glass transition temperature (T g ≈ 130 °C) and good thermal stability (T d, 5% weight loss; N2 = 251 °C, air = 217 °C). Reversible addition–fragmentation chain transfer (RAFT) polymerization of AMI using a new chain transfer agent, hydroxyethyl 4-cyano-4-(phenylcarbonothioylthio)­pentanoate (HO-CPAD), yielded PAMI-CTA samples with controlled molar masses and narrow molar mass distributions ( Đ ≤ 1.09). Subsequent chain extension of PAMI-CTA with n-butyl acrylate gave a series of PAMI-b-PnBA block copolymers ranging from 17–36 wt % PAMI. All samples of PAMI-b-PnBA exhibited two well-separated T g values at approximately −45 and +120 °C, indicative of microphase separation.

The current national priority for systemic approaches to the reform of science and mathematics education has led to unprecedented interest in research on the efficacy of science and mathematics teacher preparation programs. In response to this priority, a focus on collaborative approaches to educational reform and to research on educational reform resulted in a national collaborative research consortium of insitutions of higher education. The consortium was formed to investigate the following question about secondary science teacher education: What are the perceptions, beliefs, and classroom performances of beginning secondary teachers as related to their philosophies of teaching and their content pedagogical skills? The research design and instrumentation yielded detailed descriptions that elicited knowledge and beliefs held by beginning teachers about science, the nature of teaching and learning, and their philosophy of teaching. An analysis of video portfolios of beginning teachers provided classroom-based evidence of their performance in both subject matter and pedagogical dimensions of teaching. Among the findings from this 3-year exploratory study were that teachers graduated from their teacher preparation programs with a range of knowledge and beliefs about: how teachers should interact with subject content and processes, what teachers should be doing in the classroom, what students should be doing in the classroom, philosophies of teaching, and how they perceived themselves as classroom teachers. Beginning teachers described their practices as very student-centered. Observations of these teaching practices contrasted starkly with teacher beliefs: While teachers professed student-centered beliefs, they behaved in teacher-centered ways. Undertaking intensive, collaborative studies such as the one described in this article, is the beginning of efforts through which the science and mathematics education communities can strive to address the needs of students, teachers, teacher educators, and other stakeholders working to establish a common vision for excellent instruction and systemic, long-lasting reform. © 1999 John Wiley & Sons, Inc. J Res Sci Teach 36: 930 -954, 1999 Albert Shanker, former president of the American Federation of Teachers (AFT), testified ". . . In an enterprise such as education . . . research is the best hope we have of distinguishing between fads and facts, prejudices and informed judgment, habits and insights. Without systematic inquiry, development, and testing, we will continue to have the same babble of arguments and practices concerning what works or ought to work. Without good research, we will continue on an endless cycle of mistakes . . . an endless reinvention of mousetraps, the same rehashing of controversies, and in the end, the same faltering school system" (AFT conference, 1993). The current national priority for systemic approaches to the reform of science and mathematics education has led to unprecedented interest in research on the efficacy of science and m...

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