FTIR spectroscopic studies of interfacial reactions between amino functionalized silicon surfaces and molten maleic anhydride copolymers

Abstract

SUMMARY: The interactions of two reactive maleic anhydride copolymers, a styrene maleic anhydride copolymer and an alternating copolymer of malic anhydride and a-olefin side chains, with amino-functionalized surfaces were studied by means of FTIR-ATR spectroscopy. The interfacial processes were detected at a planar surface of a thermally oxidized silicon as internal reflecting element. This ATR element can be understood as a model for a glass fiber which is used as reinforcing material in polymer matrices. A typical glass fiber coupling agent, c-aminopropyltriethoxysilane (c-APS), was used to functionalize the silicon dioxide layer. It was found that the amino groups of the amino siloxane network layer, which were obtained by a coating procedure with c-APS, react with the anhydride groups of the copolymer melt to form amic acid structures and imide structures depending on the chemical composition of the copolymers and the temperature.

Influence of Chemical Interactions on the Macroscopic Spreading of a Maleic Anhydride Copolymer Melt

“…The success of this thermal treatment was determined by FT-IR spectroscopy. [4] c-APS was obtained from Aldrich and used as received.…”

“…By FT-IR ATR spectroscopy it could be shown that this layer consists of a highly crosslinked aminosiloxane network containing NH 2 -and NH 3 + -functional groups. [4] The mean roughness of these surfaces determined from images of 10 lm 6 10 lm was in the order of several nanometers (S a L 5 nm) compared to the bare silicon wafers having a mean roughness of S a = 0.5 nm. Contact angle measurements yielded an advancing water contact angle of 61.5 l 1.6 8 and receding angles of about 30 8.…”

“…In a previous study, we have investigated the interactions of two reactive maleic anhydride copolymers with amino-functionalized surfaces using FT-IR ATR spectroscopy. [4] It was shown that the amino groups of an aminosiloxane network layer, obtained by a coating procedure with c-APS, react with the anhydride groups of the copolymer melts to form amic acid and imide structures. Further, we showed that steric hindrance, temperature, and chemical composition of the copolymer had a higher influence on the interfacial reactions than on the corresponding bulk reactions.…”

Study on interfacial adhesion strength of single glass fibre/polypropylene model composites by altering the nature of the surface of sized glass fibres

“…2b), the absorbance bands at 2923 and 2852 cm -1 are assigned to asymmetric and symmetric stretching vibration of >CH 2 , the strong and broad peak at 1029 cm -1 is the typical stretching absorbance band of Si-O-Si. The absorbance bands between 1650~1130 cm -1 are attributed to the stretching vibration of carbonyl group and bicarbonate salts due to the interaction between the amino group of γ-APS based components and environmental CO 2 and water Page 8 of 22 [34,35]. From the similarity between Fig.…”

Affecting glass fibre surfaces and composite properties by two stage sizing application

“…It is noted that θ a of APS fibre is about 83.5°. This value is higher than the expected one (40-68°) [40,41] but still reasonable basing on following two reasons. (i) It was proposed that the electron pair on the amine nitrogen could point toward the glass surface, sideways, or toward free air [3, 26-28, 34, 42-44].…”