Enhancing thermal dimensional stability of polyimide composite films through in-situ constructing highly interfacial grafting degree to constrain early chain relaxation

In order to improve the value-added applications of low-quality wood, a novel Wood-Polymer Composite was fabricated by in-situ synthesis of copolymer from monomers within wood porous structure. The structure was characterized with SEM and FTIR, and its dimensional stability was also tested. The SEM observations showed that copolymer filled up wood pores and contact tightly with wood matrix, indicating strong interactions between them. FTIR analysis indicated that when the monomers copolymerized in situ wood porous structure, they also reacted with wood matrix by reaction of hydroxyl groups and ester groups, indicating chemical bond between the two phases, which is agreement with SEM observations. The volume swelling efficiency and contact angle of such composite were higher than those of wood, respectively, indicating good dimensional stability involving volume swelling efficiency and contact angle. Such composite could be potentially applied in fields of construction, traffic and indoor decoration.

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Preparation of Supported Zeolite Films and Layers: Processing of Zeolite Suspensions and In Situ Growth from Homogeneous Solutions

MRS Proceedings ◽

10.1557/proc-431-225 ◽

1996 ◽

Vol 431 ◽

Cited By ~ 11

Author(s):

Mark C. Lovallo ◽

Laura Boudreau ◽

Michael Tsapatsis

Keyword(s):

High Selectivity ◽

Porous Alumina ◽

Composite Films ◽

In Situ Growth ◽

Good Adhesion ◽

Homogeneous Solutions ◽

Zeolite L ◽

Alumina Composite ◽

Zeolite Films

AbstractThe influence of microstructure on the properties of zeolite films and means of controlling the former (film thickness, crystal orientation) are the theme of this report. Firstly, the formation of thin silicalite films from regrowth of nanocrystalline silicalite/alumina composite films is presented. The crystallites at the intergrown top layer are oriented with their straight channels parallel to the substrate film. The membranes show H2/N2 selectivities of about 60 at 150 °C.This high selectivity is attributed to the orientation of the separating layer. Secondly, the formation of oriented multilayers of zeolite L crystallites by alternating dippjpg of a glass substrate in a bohemite and a “plate-like” zeolite L suspensions is illustrated. Finally, continuous films of zeolite NaA are prepared on various substrates (glass, porous and nonporous alumina) using in situ growth from homogeneous solutions. The films exhibit good adhesion to the substrates. The films prepared on porous alumina disks show He/N2 and O2/N2 selectivities of 10 and 0.4 respectively at 120 °C.

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Polyimide/metal composite films via in situ decomposition of inorganic additives: Soluble polyimide versus polyimide precursor

Journal of Materials Research ◽

10.1557/jmr.1988.0996 ◽

1988 ◽

Vol 3 (5) ◽

pp. 996-1001 ◽

Cited By ~ 3

Author(s):

J. D. Rancourt ◽

G. M. Porta ◽

E. S. Moyer ◽

D. G. Madeleine ◽

L. T. Taylor

Keyword(s):

Metal Oxide ◽

Composite Films ◽

Metal Composite ◽

Air Interface ◽

Reaction Matrix ◽

Soluble Polyimide ◽

Metal Migration ◽

In Situ Decomposition ◽

Polyimide Precursor

Polyimide-metal oxide (Co3O4 or CuO) composite films have been prepared via in situ thermal decomposition of cobalt (II) chloride or bis (trifluoroacetylacetonato) copper (II). A soluble polyimide (XU-218) and its corresponding prepolymer (polyamideacid) were individually employed as the reaction matrix. The resulting composites exhibited a greater metal oxide concentration at the air interface with polyamideacid as the reaction matrix. The water of imidization that is released during the concurrent polyamide acid cure and additive decomposition is believed to promote metal migration and oxide formation. In contrast, XU-218 doped with either HAuCl4 · 3H2O or AgNO3 yields surface gold or silver when themolyzed (300 °C).

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In-Situ Characterization of Carbon Nanotube-Polystyrene Composite Deformation

Microscopy and Microanalysis ◽

10.1017/s1431927600032694 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 40-41

Author(s):

D. Qian ◽

E. C. Dickey ◽

R. Andrews ◽

T. Rantell ◽

B. Safadi

Keyword(s):

Carbon Nanotubes ◽

Load Transfer ◽

Electronic Materials ◽

Composite Films ◽

Chemical Vapor ◽

Ex Situ ◽

In Situ Tem ◽

Multiwalled Carbon ◽

Young’S Moduli

Carbon nanotubes (NTs) have novel electronic properties and exceptionally high Young's moduli on the order of TPa. so NTs have potential applications in advanced composite materials such as conductive polymers, electromagnetic-radio frequency interference (EMI/RFI) shielding material and opto-electronic materials. The utility of the nanotubes in composite applications depends strongly on the ability to disperse the NTs homogeneously throughout the matrix without destroying the integrity of the NTs. Furthermore, interfacial bonding between the NT and matrix is necessary to achieve load transfer across the interface, which is desirable for improving the mechanical properties of polymer composites.In this work, aligned multiwalled carbon nanotubes (MWNTs) produced by continuous chemical vapor deposition (CVD) (see Fig.l), were homogeneously dispersed in polystyrene (PS) matrices by a simple solution-evaporation method. Using this procedure, we made uniform MWNT-PS composite films ∼0.4mm thick for ex-situ mechanical tensile test and very thin films, ∼100nm, for in-situ TEM tests, as shown in Fig.2.

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Preparation and characterization of cellulose/in situ generated silver nanoparticle composite films prepared using Pongamia pinnata leaf extract as a reducing and stabilizing agent

Inorganic and Nano-Metal Chemistry ◽

10.1080/24701556.2020.1822869 ◽

2020 ◽

pp. 1-7

Author(s):

M. Kishanji ◽

G. Mamatha ◽

D. Madhuri ◽

D. Suresh Kumar ◽

G. Vijaya Charan ◽

...

Keyword(s):

Silver Nanoparticle ◽

Leaf Extract ◽

Composite Films ◽

Pongamia Pinnata ◽

Stabilizing Agent

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PDMS-Au/Ag Nanocomposite Films as Highly Sensitive SERS Substrates

Proceedings ◽

10.3390/proceedings2131060 ◽

2018 ◽

Vol 2 (13) ◽

pp. 1060 ◽

Cited By ~ 1

Author(s):

Attila Bonyár ◽

Zsanett Izsold ◽

Alexandra Borók ◽

István Csarnovics ◽

László Himics ◽

...

Keyword(s):

Nitrate Solution ◽

Composite Films ◽

Silver Nitrate Solution ◽

Nanocomposite Films ◽

Chloroauric Acid ◽

Technological Parameters ◽

Simple Method ◽

Sers Substrates ◽

Gold Silver

Polydimethylsiloxane (PDMS)–gold/silver nanoparticle composite films were synthetized in situ by using a simple method, which is based on the reduction of chloroauric acid (HAuCl4) or silver nitrate solution (AgNO3) by the PDMS membrane. A method to monitor the development of the plasmonic absorbance peak in situ (during the synthesis of the nanoparticles) is introduced in order to provide a convenient way to investigate the effect of the technological parameters on the position of the resulting peak. The resulting composite films were tested as SERS substrates at two excitation wavelengths (488 nm, 785 nm) and the preliminary results indicate that they are promising candidates for this application, with high sensitivities accompanied by cheap fabrication costs.

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