Plasma polymerization using pulsed microwave power

Abstract

SYNOPSISPulsed microwave power was used to polymerize a variety of monomers containing different functional groups. We examined the effects of pulse frequency and duty cycle on the deposition rates and the composition of the polymers. For monomers that do not contain oxygen we find that there is an increase in deposition rate with increasing pulse frequency and that the pulsed deposition rate is always less than the continuous power deposition rate. For monomers that contain oxygen, or for co-depositions of hydrocarbon monomers with O2 or CO, we find that there is a decrease in deposition rate with increasing frequency, however the deposition rate using pulsed power is greater than the rate using continuous power. This result is shown to be related to the amount of etching that takes place during the deposition process. Infrared studies reveal that pulsed power can alter the composition of plasma polymers of some oxygen-containing monomers. The presence or absence of vinyl unsaturation, nitrile groups, or a cyclic structure have no effect on the polymerization process.

Modification of polysulfone membranes. 2. Plasma grafting and plasma polymerization of acrylic acid

“…Acrylic acid plasma polymerization and copolymerization was a subject of several papers [29][30][31][32][33][34][35][36]. Some authors claim that level of functionality and chemical structure retention in the deposit can be controlled by the plasma deposition power [36].…”

Internal stress in plasma polymer films prepared by cascade arc torch polymerization

“…Pulsed plasma is of interest because it can control the generation rate of energetic species and thus limits the fragmentation of monomers during the time that the power is off. 14,15 A recent study by Chen et al 16 showed that the polarity and value of bias have a considerable effect on the structure of plasma polymerized styrene. The use of highmonomer flow rate is another way of limiting the damage inflicted on the monomer structure in a glow discharge.…”

Polycarbonate/Montmorillonite Nanocomposites Prepared by Microwave‐Aided Solid State Polymerization

“…The temperature profile at a given time in a microwave-heated material will depend on the dielectric properties, specific heats and thermal conductivities of the material constituents. [31,32] There are many reports that reactions of organic and organometallic compounds can be carried out with a reaction rate enhanced up to 1300 times. Another advantage of microwave irradiation is the superior morphological properties due to dielectric heating.…”

“…Another advantage of microwave irradiation is the superior morphological properties due to dielectric heating. [28][29][30][31][32][33][34] Our previous reports show that microwave solid-state polymerization is applicable not only to poly(ethylene terephthalate) (PET) or nylon but also to polycarbonate. [12,13] Microwave solid-state polymerized PC has very high molecular weight of over 40 000 g/mol, within 6 h. This method reduces reaction time exceptionally, compared to conventional solid-state polymerized PC using oil heating.…”

“…The dielectric properties, which govern the rate of internal heating, may vary widely in magnitude among the various constituents in the product, and are also functions of temperature. The temperature profile at a given time in a microwave‐heated material will depend on the dielectric properties, specific heats and thermal conductivities of the material constituents 31,32. There are many reports that reactions of organic and organometallic compounds can be carried out with a reaction rate enhanced up to 1300 times.…”