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Langmuir

Title:		Temperature and exposure dependence of hybrid organic-inorganic layer formation by sequential vapor infiltration into polymer fibers
Author(s):		Akyildiz HI; Padbury RP; Parsons GN; Jur JS;
Address:		"Department of Textile Engineering, Chemistry and Science, North Carolina State University, Raleigh, 27695, United States"
Journal Title:		Langmuir
Year:		2012
Volume:		20121023
Issue:		44
Page Number:		15697 - 15704
DOI:		10.1021/la302991c
ISSN/ISBN:		1520-5827 (Electronic) 0743-7463 (Linking)
Abstract:		"The characteristic processing behavior for growth of a conformal nanoscale hybrid organic-inorganic modification to polyamide 6 (PA6) by sequential vapor infiltration (SVI) is demonstrated. The SVI process is a materials growth technique by which exposure of organometallic vapors to a polymeric material promotes the formation of a hybrid organic-inorganic modification at the near surface region of the polymer. This work investigates the SVI exposure temperature and cycling times of sequential exposures of trimethylaluminum (TMA) on PA6 fiber mats. The result of TMA exposure is the preferential subsurface organic-inorganic growth by diffusion into the polymer and reaction with the carbonyl in PA6. Mass gain, infrared spectroscopy, and transmission electron microscopy analysis indicate enhanced materials growth and uniformity at lower processing temperatures. The inverse relationship between mass gain and exposure temperature is explained by the formation of a hybrid layer that prevents the diffusion of TMA into the polymer to react with the PA6 upon subsequent exposure cycles. As few as 10 SVI exposure cycles are observed to saturate the growth, yielding a modified thickness of approximately 75 nm and mass increase of approximately 14 wt %. Removal of the inherent PA6 moisture content reduces the mass gain by approximately 4 wt % at low temperature exposures. The ability to understand the characteristic growth process is critical for the development of the hybrid materials fabrication and modification techniques"
Keywords:		Aluminum/*chemistry Caprolactam/*analogs & derivatives/chemistry Organometallic Compounds/*chemistry Particle Size Polymers/*chemistry Surface Properties *Temperature Volatilization;
Notes:		"MedlineAkyildiz, Halil I Padbury, Richard P Parsons, Gregory N Jur, Jesse S eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2012/10/12 Langmuir. 2012 Nov 6; 28(44):15697-704. doi: 10.1021/la302991c. Epub 2012 Oct 23"