Electron Beam-Mediated Cross-Linking of Blown Film-Extruded Biodegradable PGA/PBAT Blends toward High Toughness and Low Oxygen Permeation

2022 ◽  
Author(s):  
Paresh Kumar Samantaray ◽  
Christopher Ellingford ◽  
Stefano Farris ◽  
Donal O’Sullivan ◽  
Bowen Tan ◽  
...  
Keyword(s):  
Electron Beam ◽  
Oxygen Permeation ◽  
Cross Linking ◽  
Low Oxygen ◽  
High Toughness ◽  
Blown Film

Smart membranes by electron beam cross-linking of copolymer microgels

Soft Matter ◽  
2021 ◽  
Author(s):  
Johannes Bookhold ◽  
Lars Wiehemeier ◽  
Maxim Dirksen ◽  
Sebastian Knust ◽  
Dario Anselmetti ◽  
...  
Keyword(s):  
Electron Beam ◽  
Cross Linking ◽  
Colloidal Gels ◽  
Free Standing ◽  
Copolymer Microgels

Poly(N-isopropylacrylamide) (pNIPAM) based copolymer microgels were used to create free-standing, transferable, thermoresponsive membranes. The microgels were synthesized by copolymerization of NIPAM with N-benzylhydrylacrylamide (NBHAM). Monolayers of these colloidal gels were...

Surface and Adhesive Properties of Low-Density Polyethylene after Radiation Cross-Linking

2014 ◽  
Vol 606 ◽  
pp. 265-268 ◽  
Author(s):  
Martin Bednarik ◽  
David Manas ◽  
Miroslav Manas ◽  
Martin Ovsik ◽  
Jan Navratil ◽  
...  
Keyword(s):  
Electron Beam ◽  
High Performance ◽  
Chemical Properties ◽  
Low Density Polyethylene ◽  
Cross Linking ◽  
Low Density ◽  
X Rays ◽  
Radiation Processing ◽  
Adhesive Properties ◽  
Γ Rays

Radiation cross-linking gives inexpensive commodity plastics and technical plastics the mechanical, thermal, and chemical properties of high-performance plastic. This upgrading of the plastics enables them to be used in conditions which they would not be able to with stand otherwise. The irradiation cross-linking of thermoplastic materials via electron beam or cobalt 60 (gammy rays) is performed separately, after processing. Generally, ionizing radiation includes accelerated electrons, gamma rays and X-rays. Radiation processing with an electron beam offers several distinct advantages when compared with other radiation sources, particularly γ-rays and x-rays. The process is very fast, clean and can be controlled with much precision. There is no permanent radioactivity since the machine can be switched off. In contrast to γ-rays and x-rays, the electron beam can steered relatively easily, thus allowing irradiation of a variety of physical shapes. The energy-rich beta rays trigger chemical reactions in the plastics which results in networking of molecules (comparable to the vulcanization of rubbers which has been in industrial use for so long). The energy from the rays is absorbed by the material and cleavage of chemical bonds takes place. This releases free radicals which in next phase from desired molecular bonds. This article describes the effect of radiation cross-linking on the surface and adhesive properties of low-density polyethylene.

scholarly journals Improvements of glycol methacrylate. I. Its use as an embedding medium for electron microscopic studies.

1977 ◽  
Vol 25 (3) ◽  
pp. 163-174 ◽  
Author(s):  
R C Spaur ◽  
G C Moriarty
Keyword(s):  
Electron Beam ◽  
Water Soluble ◽  
Cross Linking ◽  
Electron Microscopic ◽  
Glycol Methacrylate ◽  
Ultrastructural Studies ◽  
Tissue Morphology ◽  
Methacrylate Monomer ◽  
Microscopic Studies ◽  
Embedding Medium

The technique for using the water-soluble embedding medium glycol methacrylate has been improved for ultrastructural studies by the simplification of the method of formation of prepolymers used in embedding the tissue, by the addition of a cross-linking agent so that sections are stable in the electron beam, and by improving the softness of the blocks by the addition of a plasticizing agent. The preservation of tissue morphology has been improved by complete dehydration in glycol methacrylate monomer prior to infiltration with the prepolymer. Preservations of tissue morphology is further enhanced by complete dehydration in ethanols and embedding in the improved glycol methacrylate medium.

scholarly journals Optically transparent, high-toughness elastomer using a polyrotaxane cross-linker as a molecular pulley

2018 ◽  
Vol 4 (10) ◽  
pp. eaat7629 ◽  
Author(s):  
Hiroaki Gotoh ◽  
Chang Liu ◽  
Abu Bin Imran ◽  
Mitsuo Hara ◽  
Takahiro Seki ◽  
...  
Keyword(s):  
External Force ◽  
Matrix Material ◽  
Three Dimensional ◽  
Cross Linking ◽  
High Toughness ◽  
Dimensional Network ◽  
Cyclic Molecules ◽  
Optically Transparent ◽  
The Matrix ◽  
Special Challenge

An elastomer is a three-dimensional network with a cross-linked polymer chain that undergoes large deformation with a small external force and returns to its original state when the external force is removed. Because of this hyperelasticity, elastomers are regarded as one of the best candidates for the matrix material of soft robots. However, the comprehensive performance required of matrix materials is a special challenge because improvement of some matrix properties often causes the deterioration of others. For example, an improvement in toughness can be realized by adding a large amount of filler to an elastomer, but to the impairment of optical transparency. Therefore, to produce an elastomer exhibiting optimum properties suitable for the desired purpose, very elaborate, complicated materials are often devised. Here, we have succeeded in creating an optically transparent, easily fabricated elastomer with good extensibility and high toughness by using a polyrotaxane (PR) composed of cyclic molecules and a linear polymer as a cross-linking agent. In general, elastomers having conventional cross-linked structures are susceptible to breakage as a result of loss of extensibility at high cross-linking density. We found that the toughness of the transparent elastomer prepared using the PR cross-linking agent is enhanced along with its Young’s modulus as cross-linking density is increased.

Injection Molded Optical Lens Using a Heat Resistant Thermoplastic Resin with Electron Beam Cross-Linking

2010 ◽  
Vol 49 (5) ◽  
pp. 052601 ◽  
Author(s):  
Tomomi Sano ◽  
Yoshitomo Iyoda ◽  
Takayuki Shimazu ◽  
Michiko Harumoto ◽  
Akira Inoue ◽  
...  
Keyword(s):  
Electron Beam ◽  
Cross Linking ◽  
Thermoplastic Resin ◽  
Optical Lens ◽  
Heat Resistant ◽  
Injection Molded

Fabrication of High Toughness Poly(lactic acid) by Combining Plasticization with Cross-linking Reaction

2012 ◽  
Vol 51 (21) ◽  
pp. 7273-7278 ◽  
Author(s):  
Zhongjie Ren ◽  
Huihui Li ◽  
Xiaoli Sun ◽  
Shouke Yan ◽  
Yuming Yang
Keyword(s):  
Lactic Acid ◽  
Poly Lactic Acid ◽  
Cross Linking ◽  
High Toughness

scholarly journals Study on Wear and Morphological Behavior of Electron Beam Dose Irradiated Polyoxymethylene Copolymer (POM-C)

2016 ◽  
Vol 44 ◽  
pp. 19-28
Author(s):  
Md. Shahinur Rahman ◽  
Heon-Ju Lee ◽  
Jong-Keun Yang ◽  
Konstantin Lyakhov ◽  
Muhammad Athar Uddin
Keyword(s):  
Electron Beam ◽  
Wear Rate ◽  
Electron Beam Irradiation ◽  
Surface Hardness ◽  
Morphological Properties ◽  
Irradiation Condition ◽  
Cross Linking ◽  
Physical Factors ◽  
Beam Irradiation ◽  
Beam Dose

Polyoxymethylene copolymer (POM-C) is the most prominent engineering thermoplastic consisting of repeating carbon-oxygen bonds in the form of oxymethylene groups (OCH2). It is widely used to make small gear wheels, ball bearings, precision parts, automotive and consumer electronics. In this study, the POM-C round blocks were irradiated with 165 KeV electron beam energy in five doses (100, 200, 300, 500 and 700 kGy) in vacuum condition at room temperature. The wear rate, surface hardness and morphological properties of electron beam dose irradiated POM-C blocks surfaces have been analyzed using pin on disk tribometer, optical microscopy, nano-indenter, Raman spectroscopy, 3D nano surface profiler and scanning electron microscopy (SEM). The electron beam irradiation transferred the wear phenomena of unirradiated POM-C sample from the abrasive wear (plough and cracks), adhesive wear  (grooving/striation, micropitting) and scraping to mild scraping and striation for the 100 kGy dose irradiated POM-C sample due to cross-linking (macroscopic networks), chemical free radicals formations and partial physical modification (smoothness), which can be concluded from tribometer, optical microscopic, SEM and Raman spectroscopic observations. It also reduced the surface wear rate and average surface roughness with increasing microsurface hardness at threshold value of cross-linking among all unirradiated and others doses irradiated POM-C blocks. The level of tribological (wear and morphology) attribute improvement relies on the electron beam irradiation condition (energy and dose rate) depending on chemical and physical factors of polymeric materials.

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