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- Plasma modification (5)
- Functional groups (3)
- Introduction of functional groups (3)
- Peel strength (3)
- Pulsed plasma (3)
- Pulsed plasma polymerization (3)
- Acrylic acid (2)
- Allyl alcohol (2)
- Allylamine (2)
- Aluminium (2)
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- Polypropylene (2)
- Reactions at polymer surfaces (2)
- r.f. pulsed plasma (2)
- Adhesion (1)
- Adhesion promoters (1)
- Adhesion promoting interlayers (1)
- Adhesion-promoting interlayers (1)
- Adhesion-promoting plasma polymer layers (1)
- Al-functional group interactions (1)
- Attenuated total reflectance-Fourier transorm infrared spectroscopy (1)
- Charcterization of homo- and copolymers (1)
- Chemical conversion of functional groups (1)
- Chemical reduction of functional groups (1)
- Co-polymers (1)
- Conducting films (1)
- Cone calorimeter (1)
- Copolymers (1)
- Degradation (1)
- Doping with metal atoms (1)
- ESCA/XPS (1)
- Encapsulation of nanoparticles (1)
- Flame retardance (1)
- Fluorination kinetics (1)
- Gas phase fluorination of PE (1)
- Grafting (1)
- Heat release (1)
- Long-term stability (1)
- Metal-polymer composites (1)
- Metal-polymer interactions (1)
- Metal-polymer interface (1)
- Oxygen low-pressure plasma treatment of polymers (1)
- PET (1)
- Photoelectron spectroscopy (1)
- Plasma (1)
- Plasma bromination (1)
- Plasma polymer (1)
- Plasma polymers with functional groups (1)
- Plasma surface treatment (1)
- Plasma treatment (1)
- Plasma-initiated copolymerization (1)
- Poly(ethylene terephthalate) (1)
- Poly(propylene) (PP) (1)
- Poly(tetrafluoroethylene) (1)
- Polyamides (1)
- Polyethylene (1)
- Polymer surfaces (1)
- Polymer-metal composites (1)
- Reactions at Polymer surfaces (1)
- Selective plasma process (1)
- Spacer (1)
- Spacers (1)
- Surface modification (1)
- Surfaces (1)
- Weathering (1)
- X-ray (1)
- X-ray photoelectron spectroscopy (1)
In contrast to other plasma modification processes of polymer surfaces, the bromination is very selective and shows a high yield in C—Br groups. The most convenient bromination process was found using bromoform, which was thus preferred to elemental bromine, allyl bromide, vinyl bromide or tert-butylbromide. The bromoform process give yields in C—Br up to 40 C—Br or more, with only 2-3% co-introduction of O-functionalities whereas allyl bromide results in yields of about 20 C—Br and more, but in more than 10% oxygen-containing by-products. C—Br groups serve as anchoring points for grafting of molecules, oligomers and pre-polymers of diole or diamine character.
The hydrolytic degradation of technical poly(ethylene terephthalate) (PET) was investigated by means of different methods such as size-exclusion chromatography (SEC), viscometry, light-scattering, thin-layer chromatography, end-group titration, and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The long-term degradation was simulated by exposing PET filament yarns to aqueous neutral conditions at 90°C for up to 18 weeks. By means of MALDI-MS and thin-layer chromatography, the formation of different oligomers was obtained during polymer degradation. As expected, an ester scission process was found generating acid terminated oligomers (H-[GT]m-OH) and T-[GT]m-OH and ethylene glycol terminated oligomers (H-[GT]m-G), where G is an ethylene glycol unit and T is a terephthalic acid unit. Additionally, the scission of the ester bonds during the chemical treatment led to a strong decrease in the number of cyclic oligomers ([GT]m). The occurrence of di-acid terminated species demonstrated a high degree of degradation.
The influence of different types of low and atmospheric pressure plasma on poly(ethylene terephthalate) (PET) has been studied in terms of changes in molar mass and molar mass distribution. Apart from a variation of plasma gases (oxygen, helium) different types of plasma (microwave, radio frequency, corona discharge) were used for the plasma surface modification. The changes in molar mass and types of functional end groups of lower molar mass products were investigated by means of matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOFMS), whereas the high-molar mass fraction was analyzed by means of size-exclusion chromatography (SEC). The formation of crosslinked products during exposure to a helium plasma, which emits preponderately energy-rich and intense ultraviolet radiation, was proved by means of thermal field-flow fractionation (ThFFF). This method combined with a multiangle laser light scattering (MALLS) detector allows detection of weakly crosslinked polymers and microgels. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1639-1648, 1998