Structure-property relationships in rubber-toughened epoxies

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.

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

Journal of Applied Polymer Science ◽

10.1002/app.1992.070441102 ◽

1992 ◽

Vol 44 (11) ◽

pp. 1883-1892 ◽

Cited By ~ 10

Author(s):

P. Laurienzo ◽

M. Malinconico ◽

E. Martuscelli ◽

G. Ragosta ◽

M. G. Volpe

Keyword(s):

Structure Property ◽

New Class ◽

Structure Property Relationships ◽

Rubber Toughened

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Structure-Property Relationships in the Toughening of Poly(Methyl Methacrylate) by Sub-Micron Size, Multiple-Layer Particles

MRS Proceedings ◽

10.1557/proc-274-17 ◽

1992 ◽

Vol 274 ◽

Cited By ~ 5

Author(s):

A. C. Archer ◽

P. A. Lovell ◽

J. McDonald ◽

M. N. Sherratt ◽

R. J. Young

Keyword(s):

Mechanical Properties ◽

Methyl Methacrylate ◽

Particle Diameter ◽

Core Size ◽

Structure Property ◽

Particle Structure ◽

Poly Methyl Methacrylate ◽

Structure Property Relationships ◽

Rubber Toughened ◽

Micron Size

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.

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Rubber-toughened epoxy loaded with carbon nanotubes: structure–property relationships

Journal of Materials Science ◽

10.1007/s10853-010-4241-x ◽

2010 ◽

Vol 45 (10) ◽

pp. 2633-2639 ◽

Cited By ~ 26

Author(s):

Maria d. M. Salinas-Ruiz ◽

Alex A. Skordos ◽

Ivana K. Partridge

Keyword(s):

Carbon Nanotubes ◽

Structure Property ◽

Structure Property Relationships ◽

Toughened Epoxy ◽

Rubber Toughened

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Structure-property relationships of PE/PP sandwiched films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126998 ◽

1987 ◽

Vol 45 ◽

pp. 454-455

Author(s):

J. Petermann ◽

G. Broza ◽

U. Rieck ◽

A. Jaballah ◽

A. Kawaguchi

Keyword(s):

Mechanical Tests ◽

Polymer Materials ◽

Ionic Crystals ◽

Structure Property ◽

Polymer Systems ◽

Structure Property Relationships ◽

Oriented Films ◽

Materials Used ◽

Polymer Laminates ◽

Heated Glass

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.

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Catalyst Halogenation Enables Rapid and Efficient Polymerizations with Visible to Near-Infrared Light

10.26434/chemrxiv.12588965 ◽

2020 ◽

Author(s):

Alex Stafford ◽

Dowon Ahn ◽

Emily Raulerson ◽

Kun-You Chung ◽

Kaihong Sun ◽

...

Keyword(s):

Near Infrared ◽

Transient Absorption ◽

Reaction Times ◽

Infrared Light ◽

Structure Property ◽

Light Emitting ◽

Structure Property Relationships ◽

Nir Light ◽

Light Intensities ◽

Emission Quenching

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.

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Structure – Property Relationships of “Gemini” Surfactants and Synergism with Hydrotropes

Tenside Surfactants Detergents ◽

10.3139/113.100325 ◽

2007 ◽

Vol 44 (1) ◽

pp. 25-33 ◽

Cited By ~ 7

Author(s):

L. Wattebled ◽

C. Note ◽

A. Laschewsky

Keyword(s):

Gemini Surfactants ◽

Structure Property ◽

Structure Property Relationships

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A Review on Camptothecin Analogs with Promising Cytotoxic Profile

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520618666180327140956 ◽

2019 ◽

Vol 18 (13) ◽

pp. 1796-1814 ◽

Cited By ~ 3

Author(s):

Sk. Abdul Amin ◽

Nilanjan Adhikari ◽

Tarun Jha ◽

Shovanlal Gayen

Keyword(s):

Cell Lines ◽

Cancer Cell ◽

Cancer Cell Lines ◽

Structure Property ◽

Cytotoxic Potential ◽

Structure Property Relationships ◽

Structure Activity ◽

Camptothecin Analogs ◽

Pharmacokinetic Properties ◽

Quantitative Structure Activity Relationships

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.

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