Synthesis and structure–property relationships of a new class of rubber-toughened PMMA

1992 ◽  
Vol 44 (11) ◽  
pp. 1883-1892 ◽  
Author(s):  
P. Laurienzo ◽  
M. Malinconico ◽  
E. Martuscelli ◽  
G. Ragosta ◽  
M. G. Volpe
Author(s):  
Barbara A. Wood

A controversial topic in the study of structure-property relationships of toughened polymer systems is the internal cavitation of toughener particles resulting from damage on impact or tensile deformation.Detailed observations of the influence of morphological characteristics such as particle size distribution on deformation mechanisms such as shear yield and cavitation could provide valuable guidance for selection of processing conditions, but TEM observation of damaged zones presents some experimental difficulties.Previously published TEM images of impact fractured toughened nylon show holes but contrast between matrix and toughener is lacking; other systems investigated have clearly shown cavitated impact modifier particles. In rubber toughened nylon, the physical characteristics of cavitated material differ from undamaged material to the extent that sectioning of heavily damaged regions by cryoultramicrotomy with a diamond knife results in sections of greater than optimum thickness (Figure 1). The detailed morphology is obscured despite selective staining of the rubber phase using the ruthenium trichloride route to ruthenium tetroxide.


1989 ◽  
Vol 29 (20) ◽  
pp. 1466-1476 ◽  
Author(s):  
J.-F. Hwang ◽  
J. A. Manson ◽  
R. W. Hertzberg ◽  
G. A. Miller ◽  
L. H. Sperling

2021 ◽  
Vol 9 (8) ◽  
pp. 4348-4378
Author(s):  
Vishnu Unnikrishnan ◽  
Omid Zabihi ◽  
Mojtaba Ahmadi ◽  
Quanxiang Li ◽  
Patrick Blanchard ◽  
...  

Metal–organic frameworks (MOFs) have emerged as a new class of crystalline nanomaterials with ultrahigh porosities and high internal surface areas.


2018 ◽  
Vol 11 (5) ◽  
pp. 1326-1334 ◽  
Author(s):  
Mingjun Huang ◽  
Shuting Feng ◽  
Wenxu Zhang ◽  
Livia Giordano ◽  
Mao Chen ◽  
...  

Fluorinated Aryl Sulfonimide Tag (FAST) anions provide a new class of modular salts with tunable properties for potential battery applications.


1992 ◽  
Vol 274 ◽  
Author(s):  
A. C. Archer ◽  
P. A. Lovell ◽  
J. McDonald ◽  
M. N. Sherratt ◽  
R. J. Young

ABSTRACTRubber-toughened poly(methyl methacrylate) materials have been prepared by blending poly(methyl methacrylate) with specially-synthesised, refractive index matched particles containing two, three and four radially-alternating rubbery and glassy layers. The paper describes the effects upon mechanical properties of (i) two-, three- and four-layer particle structure and (ii) particle diameter and glassy core size for three-layer particles.


2010 ◽  
Vol 45 (10) ◽  
pp. 2633-2639 ◽  
Author(s):  
Maria d. M. Salinas-Ruiz ◽  
Alex A. Skordos ◽  
Ivana K. Partridge

Author(s):  
J. Petermann ◽  
G. Broza ◽  
U. Rieck ◽  
A. Jaballah ◽  
A. Kawaguchi

Oriented overgrowth of polymer materials onto ionic crystals is well known and recently it was demonstrated that this epitaxial crystallisation can also occur in polymer/polymer systems, under certain conditions. The morphologies and the resulting physical properties of such systems will be presented, especially the influence of epitaxial interfaces on the adhesion of polymer laminates and the mechanical properties of epitaxially crystallized sandwiched layers.Materials used were polyethylene, PE, Lupolen 6021 DX (HDPE) and 1810 D (LDPE) from BASF AG; polypropylene, PP, (PPN) provided by Höchst AG and polybutene-1, PB-1, Vestolen BT from Chemische Werke Hüls. Thin oriented films were prepared according to the method of Petermann and Gohil, by winding up two different polymer films from two separately heated glass-plates simultaneously with the help of a motor driven cylinder. One double layer was used for TEM investigations, while about 1000 sandwiched layers were taken for mechanical tests.


2020 ◽  
Author(s):  
Alex Stafford ◽  
Dowon Ahn ◽  
Emily Raulerson ◽  
Kun-You Chung ◽  
Kaihong Sun ◽  
...  

Driving rapid polymerizations with visible to near-infrared (NIR) light will enable nascent technologies in the emerging fields of bio- and composite-printing. However, current photopolymerization strategies are limited by long reaction times, high light intensities, and/or large catalyst loadings. Improving efficiency remains elusive without a comprehensive, mechanistic evaluation of photocatalysis to better understand how composition relates to polymerization metrics. With this objective in mind, a series of methine- and aza-bridged boron dipyrromethene (BODIPY) derivatives were synthesized and systematically characterized to elucidate key structure-property relationships that facilitate efficient photopolymerization driven by visible to NIR light. For both BODIPY scaffolds, halogenation was shown as a general method to increase polymerization rate, quantitatively characterized using a custom real-time infrared spectroscopy setup. Furthermore, a combination of steady-state emission quenching experiments, electronic structure calculations, and ultrafast transient absorption revealed that efficient intersystem crossing to the lowest excited triplet state upon halogenation was a key mechanistic step to achieving rapid photopolymerization reactions. Unprecedented polymerization rates were achieved with extremely low light intensities (< 1 mW/cm<sup>2</sup>) and catalyst loadings (< 50 μM), exemplified by reaction completion within 60 seconds of irradiation using green, red, and NIR light-emitting diodes.


2019 ◽  
Vol 18 (13) ◽  
pp. 1796-1814 ◽  
Author(s):  
Sk. Abdul Amin ◽  
Nilanjan Adhikari ◽  
Tarun Jha ◽  
Shovanlal Gayen

Camptothecin (CPT), obtained from Camptotheca acuminata (Nyssaceae), is a quinoline type of alkaloid. Apart from various traditional uses, it is mainly used as a potential cytotoxic agent acting against a variety of cancer cell lines. Though searches have been continued for last six decades, still it is a demanding task to design potent and cytotoxic CPTs. Different CPT analogs are synthesized to enhance the cytotoxic potential as well as to increase the pharmacokinetic properties of these analogs. Some of these analogs were proven to be clinically effective in different cancer cell lines. In this article, different CPT analogs have been highlighted extensively to get a detail insight about the structure-property relationships as well as different quantitative structure-activity relationships (QSARs) modeling of these analogs are also discussed. This study may be beneficial for designing newer CPT analogs in future.


Sign in / Sign up

Export Citation Format

Share Document