Polymer Branching Analytical.docPage 1 of 3
Bibliographic Information
Quantification of branching in disordered materials. Kulkarni, A. S.; Beaucage, G. Department of Chemical and Materials Engineering, University of Cincinnati, Cincinnati, OH, USA. Journal of Polymer Science, Part B: Polymer Physics (2006), 44(10), 1395-1405. Publisher: John Wiley & Sons, Inc., CODEN: JPBPEM ISSN: 0887-6266. Journal; General Review written in English. CAN 145:293558 AN 2006:671730 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
A review. The phenomenon of structural branching is ubiquitous in a wide array of materials: polymers, ceramic aggregates, polymeric networks, and gels. Branching has a strong influence on the structure-property relationships of these materials. Despite the interdisciplinary importance and decades of effort, the anal. description and quantification of branching are weak. Existing techniques for polymers based on size exclusion chromatog. and rheol. are, at best, qual., and quant. characterization techniques such as NMR spectroscopy and transmission electron microscopy (for ceramic aggregates) have limitations in providing routine quantification. For ceramic aggregates, theor. work has dominated, and only a few publications on anal. studies exist to support the theory. Small-angle scattering of X-rays and neutrons can be used to quantify the branch content through application of concepts native to fractal geometry.
Star polyamides. Theoretical model and industrial application. Di Silvestro, Giuseppe; Yuan, Cui Ming; Speroni, Franco; Guaita, Cesare; Zhang, Haichung. Dip. Chim. Org. Industriale, Univ. Milano, Milan, Italy. Chimica e l'Industria (Milan, Italy) (2005), 87(6), 44-48. Publisher: Promedia Publishing, CODEN: CINMAB ISSN: 0009-4315. Journal; General Review written in Italian. CAN 145:489585 AN 2006:500115 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
A review. The properties of star polyamides prepd. by condensation polymn. in the presence of multifunctional reagents are detd. by the control of chain growth. A theor. model for the chain growth process based on divergent synthesis of an A-B monomer and a multifunctional reagent is discussed. The mech. properties of star polyamides and composites with glass fibers are also discussed.
Bibliographic Information
Mass spectrometry of step-growth polymers. Klee, Joachim E. Dentsply De Trey, Konstanz, Germany. European Journal of Mass Spectrometry (2005), 11(6), 591-610. Publisher: IM Publications, CODEN: EJMSCL ISSN: 1469-0667. Journal; General Review written in English. CAN 145:293555 AN 2006:37346 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
A review. For at least two decades, different mass spectrometric techniques have been applied for polymer anal., including the qual. detn. of chem. compns., end group identification, functionality type distribution and the detn. of the extent of cyclisation at each degree of polymn. Mol. wts. exceeding 100 KDa are provable by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-ToF-MS). However, there are some hints that there is a discrimination against higher mol. wt. species in samples with polydispersity of more than 1.2. Pathways for dendritic and hyper-branched polymers, supramol. polymers and nano condensates are analyzed with the help of mass spectrometry.
Bibliographic Information
Linear and branched polymers on fractals. Dhar, Deepak; Singh, Yashwant. Department of Theoretical Physics, Tata Institute of Fundamental Research, Mumbai, India. Los Alamos National Laboratory, Preprint Archive, Condensed Matter (2005), 1-46, arXiv:cond-mat/0508330. Publisher: Los Alamos National Laboratory, CODEN: LNCMFR Preprint; General Review written in English. CAN 144:331995 AN 2005:843737 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
This is a pedagogical review of the subject of linear polymers on deterministic finitely ramified fractals. For these, one can det. the crit. properties exactly by real-space renormalization group technique. We show how this is used to det. the crit. exponents of self-avoiding walks on different fractals. The behavior of crit. exponents for the n-simplex lattice in the limit of large n is detd. We study self-avoiding walks when the fractal dimension of the underlying lattice is just below 2. We then consider the case of linear polymers with attractive interactions, which on some fractals leads to a collapse transition. The fractals also provide a setting where the adsorption of a linear chain near on attractive substrate surface and the zipping-unzipping transition of two mutually interacting chains can be studied anal. We also discuss briefly the crit. properties of branched polymers on fractals.
Bibliographic Information
SEC molecular-weight-sensitive detection. Mourey, Thomas. Imaging Materials and Media, Research and Development Laboratories, Eastman Kodak Company, Rochester, NY, USA. International Journal of Polymer Analysis and Characterization (2004), 9(1-3), 97-135. Publisher: Taylor & Francis, Inc., CODEN: IPACEZ ISSN: 1023-666X. Journal; General Review written in English. CAN 142:447568 AN 2005:32132 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
This review examines many of the specific applications of size-exclusion chromatog. (SEC) to polymers described in publications since 2001 and also gives an updated view of the basic principles of viscometry and elastic light scattering mol.-wt.-sensitive detectors for SEC. These include the use of multidetector systems for validating SEC fractionation, examg. polymer conformation, quantifying many forms of polymer topol. (e.g., branching), physiochem. studies (e.g., phase sepn. and aggregation), analyzing oligomers, assessing polymer optical anisotropy, and estg. second virial coeffs. Although multidetector SEC is not without sources of error and uncertainty, it has developed into an extremely powerful anal. method that is increasingly used to accomplish diverse and difficult polymer analyses.
Bibliographic Information
Size-exclusion chromatography with dynamic surface tension detection: Analysis of polymers and proteins. Synovec, Robert E.; Staggemeier, Bethany A.; Bramanti, Emilia; Quigley, Wes W. C.; Prazen, Bryan J. Department of Chemistry, Center for Process Analytical Chemistry, University of Washington, Seattle, WA, USA. ACS Symposium Series (2005), 893(Multiple Detection in Size-Exclusion Chromatography), 266-280. Publisher: American Chemical Society, CODEN: ACSMC8 ISSN: 0097-6156. Journal; General Review written in English. CAN 143:306733 AN 2005:19086 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
A review. Multidimensional anal. of linear and branched polymers and proteins by size exclusion chromatog. with dynamic surface tension detection is presented. In particular, the application of this hyphenated chromatog. technique is applied to the anal. and characterization of poly(ethylene) glycol (PEG) polydispersity, mol. sizing of branched PEGs, and sepn. and anal. of protein samples. Benefits of multidimensional chromatog. detection for SEC and selective surface activity anal. are briefly discussed. The dynamic nature of the surface tension signal provides addnl. chem. information and selectivity.
Bibliographic Information
Establishing structure-property relationships using materials with linear and star-branched macrostructures. Henning, Steven K. Chemical Division, Polymer Product Development, The Goodyear Tire & Rubber Company, Akron, OH, USA. Technical Papers - American Chemical Society, Rubber Division, [Fall Technical Program], 164th, Cleveland, OH, United States, Oct. 14-17, 2003 (2003), 902-966. Publisher: American Chemical Society, Rubber Division, Akron, Ohio CODEN: 69EZYK Conference; General Review; Computer Optical Disk written in English. CAN 141:278768 AN 2004:103385 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
A review. Establishing structure-property relationships between polymer macrostructure and compd. performance and processing characteristics is an important step in the development of new elastomeric products which are designed for special applications. By analyzing the rheol. behavior of model elastomer samples displaying extremes of branch type and content, a model for the rheol. behavior of com. produced materials can be developed. The use of anionic polymn. techniques to incorporate branching in polymn. systems that otherwise produce linear products is discussed. In addn., the mol. theories governing the rheol. of entangled polymer chains are reviewed with an emphasis on branched structures. Anionic soln. techniques were used to produce poly(butadienes) (PBDs) with well-defined macrostructures. The macrostructure was detd. in soln. by multi-angle laser light scattering and soln. viscometry. The rheol. behavior of the bulk samples was explored by oscillatory shear testing under various conditions. The star-branched samples displayed smaller radii of gyration and lower soln. viscosities than their linear counterparts at equiv. mol. wt. The rheol. behavior of the branched samples also differed significantly. Finally, com. samples of continuously-produced soln. poly(styrene-co-butadiene) rubbers (SSBRs) were used to validate structure-property relationships in filled compds. The star-branched products exhibit improved processing at the expense of higher hysteresis.
Bibliographic Information
Hyperbranched polymers: a chance and a challenge. Voit, Brigitte I. Institut fur Polymerforschung Dresden e.V., Dresden, Germany. Comptes Rendus Chimie (2003), 6(8-10), 821-832. Publisher: Editions Scientifiques et Medicales Elsevier, CODEN: CRCOCR ISSN: 1631-0748. Journal; General Review written in English. CAN 140:181830 AN 2003:877334 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
A review on hyperbranched polymers in which examples out of a broad variety of structures are discussed as well as several possible applications. It is demonstrated that the structure of hyperbranched polymers with all different structural units can be fully clarified which allows the detn. of the degree of branching, verification of side reactions, as well as considerations regarding reaction mechanism and kinetics of the branching process. By modification of the end groups the properties of hyperbranched polymers are significantly detd. and define possible applications.
Bibliographic Information
Gel permeation/liquid chromatography: a powerful tool in polymer analysis. Maiti, Sukumar. Materials Science Centre, Indian Institute of Technology, Kharagpur, India. Editor(s): Maiti, Sukumar. Analysis and Characterization of Polymers (2003), 133-139. Publisher: Anusandhan Prakashan, Midnapore, India CODEN: 69EFGA Conference; General Review written in English. CAN 140:199943 AN 2003:554710 CAPLUS (Copyright (C) 2007 ACS on SciFinder (R))
Abstract
A review on the principle of gel permeation chromatog. and its applications in polymer anal. Gel permeation chromatog. is a useful technique for analyzing copolymer compn. and type of branching of a polymer, evaluating catalyst effect on polymer, monitoring the course of polymn., assessing the quality of the raw material resin, and for analyzing polymer additives.