Effect of molecular weight on the surface morphology of crosslinked polymer particles in the RITP-dispersion polymerization

The term “gel”, in the jargon of the plastics film industry, may refer to any inclusion that produces a visible artifact in a polymeric film. Although they can occur in any plastic product, gels are a principle concern in films where they detract from the cosmetic appearance of the product and may compromise its mechanical strength by acting as local stress concentrators. Many film gels are small spheres or ellipsoids less than one millimeter in diameter whereas other gels are fusiform-shaped and may reach several centimeters in length. The actual composition of gel inclusions may vary from miscellaneous inorganics (i.e. glass and mineral particles) and processing additives to heavily oxidized, charred or crosslinked polymer. The most commonly observed gels contain polymer differing from the bulk of the sample in its melt viscosity, density or molecular weight.Polymeric gels are a special concern in polyethylene films. Over the years and with the examination of a variety of these samples three predominant polymeric species have been observed: density gels which have different crystallinity than the film; melt-index gels in which the molecular weight is different than the film and crosslinked gels which are comprised of crosslinked polyethylene.

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Hard Coating Materials Based on Photo-Reactive Silsesquioxane for Flexible Application: Improvement of Flexible and Hardness Properties by High Molecular Weight

Polymers ◽

10.3390/polym13101564 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1564

Author(s):

Jong Tae Leem ◽

Woong Cheol Seok ◽

Ji Beom Yoo ◽

Sangkug Lee ◽

Ho Jun Song

Keyword(s):

Molecular Weight ◽

Surface Morphology ◽

High Molecular Weight ◽

Sol Gel ◽

Xrd Analysis ◽

Polyhedral Oligomeric Silsesquioxanes ◽

Coating Materials ◽

Pencil Hardness ◽

Coated Film ◽

Flexible Application

EPOSS of polyhedral oligomeric silsesquioxanes (POSS) mixture structure and LPSQ of ladder-like polysilsesquioxane (LPSQ) structure were synthesized via sol–gel reaction. EPSQ had a high molecular weight due to polycondensation by potassium carbonate. The EPSQ film showed uniform surface morphology due to regular double-stranded structure. In contrast, the EPOSS-coated film showed nonuniform surface morphology due to strong aggregation. Due to the aggregation, the EPOSS film had shorter d-spacing (d1) than the EPSQ film in XRD analysis. In pencil hardness and nanoindentation analysis, EPSQ film showed higher hardness than the EPOSS film due to regular double-stranded structure. In addition, in the in-folding (r = 0.5 mm) and out-folding (r = 5 mm) tests, the EPSQ film did not crack unlike the EPOSS coated film.

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Chitosan hydrogels embedding hyper-crosslinked polymer particles as reusable broad-spectrum adsorbents for dye removal

Carbohydrate Polymers ◽

10.1016/j.carbpol.2017.09.006 ◽

2017 ◽

Vol 177 ◽

pp. 347-354 ◽

Cited By ~ 39

Author(s):

Martina Salzano de Luna ◽

Rachele Castaldo ◽

Rosaria Altobelli ◽

Lucia Gioiella ◽

Giovanni Filippone ◽

...

Keyword(s):

Broad Spectrum ◽

Dye Removal ◽

Polymer Particles ◽

Crosslinked Polymer ◽

Chitosan Hydrogels

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RGD-decorated conjugated polymer particles as fluorescent biomedical probes prepared by Sonogashira dispersion polymerization

Chemical Communications ◽

10.1039/c4cc10092a ◽

2015 ◽

Vol 51 (45) ◽

pp. 9358-9361 ◽

Cited By ~ 18

Author(s):

Naveed Anwar ◽

Anne Rix ◽

Wiltrud Lederle ◽

Alexander J. C. Kuehne

Keyword(s):

Click Chemistry ◽

Fluorescent Probes ◽

Conjugated Polymer ◽

Dispersion Polymerization ◽

Cell Labelling ◽

Polymer Particles ◽

Free Thiol ◽

One Step

We present a one-step Sonogashira dispersion polymerization generating monodisperse conjugated polymer particles with acetylene units on their surface. These moieties can be bio-functionalized using copper-free thiol-yne click chemistry providing fluorescent probes for cell labelling and imaging.

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