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Roll-to roll Initiated Chemical Vapor Deposition of Super Hydrophobic Thin
Films on Large-Scale Flexible Substrates
Hüseyin Şakalak, Kurtuluş Yılmaz, Mehmet Gürsoy, Mustafa Karaman
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https://doi.org/10.1016/j.ces.2019.115466
CES 115466
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Chemical Engineering Science
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31 December 2019
Please cite this article as: H. Şakalak, K. Yılmaz, M. Gürsoy, M. Karaman, Roll-to roll Initiated Chemical Vapor
Deposition of Super Hydrophobic Thin Films on Large-Scale Flexible Substrates, Chemical Engineering Science
(2019), doi: https://doi.org/10.1016/j.ces.2019.115466
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Roll-to roll Initiated Chemical Vapor Deposition of Super Hydrophobic Thin Films on
Large-Scale Flexible Substrates
Hüseyin Şakalaka, Kurtuluş Yılmazb, Mehmet Gürsoy1,b,*, Mustafa Karaman1,b,*
a
Advanced Materials and Nanotechnology Department, Selcuk University, 42075, Turkey
Engineering Department, Konya Technical University, Konya, 42030, Turkey
b Chemical
*Corresponding
Authors:
E-mail: [email protected], [email protected]
Phone: +(90) 332 223 2145, +(90) 332 223 2108
Fax:
+(90) 332 241 0635
Postal address: Department of Chemical Engineering, Konya Technical University, Campus,
Konya 42030, Turkey
1
These corresponding authors have made equal contributions.
Abstract
In this study, a large-scale roll-to-roll initiated chemical vapor deposition (iCVD) system was
developed to allow for coating superhydrophobic thin films on flexible substrates.
Poly(hexafluorobutyl acrylate), which possesses a short fluorinated side-chain, was chosen as
the hydrophobic finish material, while a commercial porous bamboo fabric was used as the
flexible substrate. After iCVD coating, bamboo surface, which is superhydrophilic by its
nature, transformed into a superhydrophobic with a water contact angle of 156° without
changing its porous and flexible structure. Similar hydrophobic properties were observed
against various daily liquids. Complete coverage of as-deposited films on both sides of
bamboo surfaces was observed at very high roll speeds up to 225 mm/min, which allow
coatings on 20 m2 flexible substrates in a single run. Large scale contact angle and chemical
uniformity of coatings on fabric surfaces were evaluated using contact angle and XPS
analyses.
Keywords: iCVD, Superhydrophobic, Roll-to-roll, Polymer, Thin film
Graphical abstract
Highlights
A roll-to-roll iCVD system was designed.
Superhydrophobic coatings were deposited on bamboo surfaces.
High roll speeds up to 225 mm/min was achieved.
As-deposited polymers were conformal and uniform.
1. Introduction
In last decades, the emergence of flexible electronics for variety of applications, such as
flexible displays, flexible circuits, flexible sensors and flexible solar cells, has led to increased
need for large-scale production processes (Dubal et al., 2018; Lee and Yoo, 2012; Yang and
Gao, 2019). Other than the electronics field, flexible substrates are used in a wide variety of
applications such as membranes, food packaging, artificial skins, microfluidics, etc (Lei and
Wu, 2019; Yang et al., 2019). In general, roll-to-roll systems are preferred to the conventional
batch systems to coat flexible substrates in a continuous manner for the mass production of
many important products (Gao et al., 2016; Guerrero et al., 2011; Maydannik et al., 2011).
When compared with the batch systems, roll-to-roll systems offer significant cost reduction
considering the high yield and large utilized surface area (Kovacik et al., 2015).
The interest in functional polymeric coatings has recently experienced rapid growth
within both the research and industrial community because of their flexible properties (Chen
et al., 2013; Gürsoy et al., 2017b). Functional coatings add desired properties on the surface
of substrates without changing the bulk. Polymer coating processes can be divided into two
main categories, namely wet and dry techniques. In the former ones, the coating material and
a suitable binder are dissolved in a solution that is directly coated on the substrate. The
evaporation of solvent from the wet film results in a dry and stringent coating on substrate
surface. Drop casting, spin coating, dip coating, sol-gel, and spray coating are among the most
utilized coatings for various applications (Danglad-Flores et al., 2018; Schlaich et al., 2018;
Wedershoven et al., 2018). In dry techniques, as its name implies, the usage of solvents is
ruled out, and coating material is directly deposited on the substrate surface through
condensation of vapor-phase precursors (Gürsoy et al., 2019). Physical vapor deposition
(PVD) and chemical vapor deposition (CVD) techniques are widely used dry techniques for
coating thin, conformal, and uniform films on many different types of substrates. Such vapor
deposition techniques are usually carried out at low substrate temperatures, and necessarily
without solvents, hence there is a wide range of substrates that can be coated using such
techniques, including the ones which are fragile and not compatible with the heat or solvents
used for wet techniques, such as paper, plastic sheets, and vulnerable electronic structures.
PVD and CVD techniques can be easily utilized in roll-to-roll processing (Gürsoy and
Karaman, 2017). Sputter coating systems are the most common, in which the substrate roll is
placed in a sputtering vacuum chamber in which it is easy to evaporate different materials
onto the flexible substrate surface. In recent decades, initiated chemical vapor deposition
(iCVD) has been shown to be a highly successful vapor-based technique in making a wide
range of polymers and for a wide range of applications (Gürsoy et al., 2017a; Kuba et al.,
2016). In iCVD, initiator molecules are fed into a reaction chamber under vacuum together
with the monomer molecules. A heated filament array is placed a few centimeters above the
substrate surface, which is used to activate the polymerization reactions by thermally
decomposing the initiator molecules into free-radicals. The substrate is cooled to promote
physical adsorption of monomer molecules, which react with the radicals originated from the
initiator molecules to deposit the desired polymer on the substrate surface. Highly conformal
coatings have been deposited on a wide range of flexible surfaces including textiles, plastic
sheets, paper, porous membranes, etc. by iCVD (Asatekin and Gleason, 2010; Baxamusa et
al., 2009; Karaman et al., 2012).
iCVD processes is easily scalable to achieve high-throughput production, making it
suitable for mass production equipment such as roll-to-roll process (Cheng and Gupta, 2018;
Gupta and Gleason, 2006). Similar scale-up procedures have been shown for some other
vapor-based chemical coating techniques such as plasma-enhanced CVD (PECVD), hotfilament CVD (HFCVD), and atomic layer deposition (ALD) (Balu et al., 2008; Elam et al.,
2017; Premkumar et al., 2010). In this study, we demonstrate the ability of iCVD to coat
large-scale textile fabric for hydrophobic functionalization of flexible textile substrates.
Fluoroalkylated polymers with long perfluorinated chains (more than eight fluorinated C)
are usually used to produce hydrophobic surfaces (Politakos et al., 2018; Virendra et al.,
2010). However, during the synthesis of long chain fluoropolymers may lead to the release of
some toxic chemicals such as perfluoroalkyl sulfonate and perfluoroalkyl acid (Jiang et al.,
2016; Liu and Avendaño, 2013). Unfortunately, release of the chemicals can adversely affect
the environment and human health due to bioaccumulative potential of them (Grandjean et al.,
2012). Moreover, it is known that there is a directly proportional relationship between the
length of perfluorinated chains and bioaccumulative potential of fluoropolymers (Olsen et al.,
2009). Taking the potential risks of fluoroalkylated polymers with long perfluorinated chains
into account, using short-chain fluorinated fluoropolymers are becoming more important. In
this study, short-chain fluorinated poly(hexafluorobutyl acrylate) (PHFBA) has been chosen
for hydrophobic surface fabrication. A horizontal large-scale roll-to-roll vacuum chamber was
designed, which is capable of handling 20-cm wide fabric rolls. Large-area uniformity of
PHFBA along different dimensions of substrate fabric was demonstrated through contact
angle and X-ray photoelectron spectroscopy (XPS).
2. Experimental
2.1.
Materials
Silicon wafer (100, p-type) and commercial bamboo fabric (non-woven, pore size is around
0.3 mm2) were used as substrates. The monomer 2,2,3,4,4,4- hexafluorobutyl acrylate
(HFBA, 95%, Sigma–Aldrich) and the initiator di-tert butyl peroxide (TBPO, 98%, Sigma–
Aldrich) were used as-received without any further modification or purification. The chemical
structures of both chemicals are given in Figure 1a. Daily liquids (milk, coffee, tea, pure apple
juice, sour cherry juice, coke) were purchased from a local market.
2.2.
Roll-to-roll iCVD of PHFBA
The schematic diagram of the experimental set-up is shown in Figure 1b. Depositions were
carried out in a custom-built stainless-steel cylindrical vacuum chamber, which was modified
to hold unwinder and rewinder rolls. The diameter of each roll is 46 mm, with maximum
width of 30 cm. A horizontal 20 cm x 30 cm stainless steel water-circulated cooling plate was
placed between the filament array and the rolls. The plate was cooled using water from a
recirculating chiller (Thermo Neslab) and circulated water was maintained at a constant
temperature adjustable between 5 and 35 °C. It is important to note that the substrate
temperatures reported in this study were measured by attaching a thermocouple on the bottom
of the fabric surface. During the depositions, the flexible bamboo fabric was passed through
contact with the cooled-surface from unwinder roll to rewinder roll with speeds between 90
mm/min and 225 mm/min, which can be tuned using a stepper motor. The rotary motion from
the stepper motor, which was placed outside the vacuum chamber, to the interior of vacuum
chamber was achieved by using a rotary feed through sealed with magnetic fluids. Vacuum
was achieved by a dry vacuum pump (Edwards XDS-10). HFBA and TBPO were evaporated
in separate jars at room temperature. Flowrates of monomer and initiator were 5.5 sccm, 4
sccm, respectively. These flow rates were kept constant in all experiments using needle valves
(Swagelock). The reactor pressure was kept constant at 1.1 Torr, which was measured and
controlled by a capacitance manometer (MKS Baratron) and a butterfly throttling valve
(MKS), respectively. All depositions were carried out at four different substrate temperature;
5 °C, 15 °C, 25 °C and 35 °C. A series of 11 parallel nichrome (Ni 80% / Cr 20%) filaments
were placed 30 mm above the cooled surface and temperature of the filaments were set at 240
°C. The filament temperature was measured by a K-type thermocouple (Omega) directly
connected to one of the filament wires.
Figure 1. HFBA monomer (a), TBPO initiator (b), schematic of roll to roll iCVD system (c)
2.3. Characterizations of PHFBA thin films
FTIR (Bruker Vertex 70) and XPS (Specs spectrophotometer with a monocromatized Al
source) were employed to analyze the chemical structure of as-deposited PHFBA thin films.
FTIR spectra were obtained at between 400 and 4000 cm-1 wavenumbers at a resolution of 4
cm-1. Obtained spectra were baseline corrected and thickness normalized. Morphological
appearances of uncoated and PHFBA coated bamboo fabric were investigated by SEM (Zeiss
LS-10). Deposition rates were monitored in-situ by measuring the changes in reflected power
off the reference silicon substrates using a 632.8 nm He-Ne laser light (633nm HeNe laser,
JDS Uniphase). Two different sets of experiments were performed. In the first set, the fabric
was stationary. In the second set, the fabric was moved at desired speeds. The deposition rate
on the moving substrate was measured by attaching small pieces of silicon wafer to fabric
surface. In that case, the thicknesses of the as-deposited films were measured ex-situ using a
reflectometer (Avaspec-ULS2048L spectrometer with AvaLight-DH-S BAL light source).
The deposition rate measurements were repeated on at least four locations of sample surfaces.
Static and dynamic water contact angle analyses of PHFBA coated bamboo fabric were
measured with contact angle goniometer system (Kruss Easy Drop) at ambient temperature
using 5.0 μL of pure water with a pH close to 7.0. Advancing and receding contact angles
were measured by increasing and decreasing the water droplet volume, respectively, until
moving the contact line between water drop and surface. The contact angle measurements
were repeated at least three times for each sample. The durability of PHFBA deposited thin
film on the bamboo fabric was tested by a standard laundering test. The laundering was
carried out at 30 °C for 30 minutes using a liquid detergent and then the fabric was dried at
room temperature. The contact angle measurements were done after three washing cycle.
Daily liquid static contact angle and tilting angle measurements were undertaken with the
other contact angle goniometer system (Model OCA 50, DataPhysics Instruments GmbH)
using droplet volume of 5.0 μL and 10.0 μL, respectively.
3. Results and discussion
3.1. iCVD of PHFBA on stationary substrate
The effect of substrate temperature on the deposition rates of PHFBA films was investigated.
For this purpose, PHFBA thin films were synthesized at four different substrate temperatures,
namely 5, 15, 25 and 35°C, while keeping all the other iCVD parameters constant.
In the first set of experiments 20 pieces of silicon wafers were directly placed onto the heat
exchanger stage at equal intervals along the coating zone, which is 20 cm in width by 30 cm
in length. In the second set, the same amount of silicon wafer pieces was placed on the
bamboo fabric surface that was in contact with the cooling plate. As seen in Figure 2 a,
deposition rates increase with decreasing substrate temperature from 35 to 5°C. In other
words, PHFBA deposition rate is inversely proportional with the substrate temperature
implying that the deposition kinetics of PHFBA is adsorption limited. This observation is in
accordance with previous PHFBA CVD literature (Karaman et al., 2017). The highest average
deposition rates of PHFBA on silicon wafer, which were placed directly on cooling plate and
on fabric surface, were found as 45.6 ± 3.8 nm/min and 10.4 ± 0.4 nm/min, respectively, at a
substrate temperature of 5°C. It is important to note here that, the deposition rates observed on
silicon wafers which were placed directly on cooling plate were higher than for those placed
on fabric at all studied substrate temperatures. The reason of this observation could be
attributed to two main reason. The first one is that the fabric placed between the wafer and
cooling plate prevents the silicon wafer from directly contacting the heat exchanger. Highly
porous bamboo fabric has poor heat conductance values, which acts as an insulator against
efficient heat transfer between cooling plate and the surface. The other reason is that Si wafer
placed on fabric is closer to the heated filament array, which makes the wafer surface warmer
as compared to samples placed directly on the cooling plate due to higher exposure to thermal
radiation from heated filament array. Since iCVD is mainly an adsorption-limited process, the
decrease in the deposition rate can be attributed to the increased surface temperature of the
substrate, when the substrate is a poor heat conductor.
Large area (20 cm x 30 cm) thickness uniformities of the iCVD PHFBA films deposited at a
substrate temperature of 5°C were investigated. The measured thicknesses were written
regarding areas shown in Figure 2 b and Figure 2 c. Since heat dissipation was more
uniformly distributed throughout the heat exchanger, more uniform film thickness (~±4.8%)
was observed on the heat exchanger as compared to that (~±8.3%) obtained from the bamboo
fabric surface.
Figure 2. PHFBA deposition rates on bamboo fabric and on cooling plate as a function of
substrate temperature (a), thickness uniformities of as-deposited films on cooling plate (b) and
bamboo fabric (c)
3.2. Roll-to-roll iCVD of PHFBA on moving substrate
In order to evaluate the effect of substrate speed on PHFBA deposition rate, PHFBA
depositions were conducted at four different substrate speed (vs) values ranging from 90
mm/min to 225 mm/min, while all other iCVD parameters were kept constant. Moreover,
depositions were also carried out on stationary substrates without turning the rolls.
Deposition rates were calculated from PHFBA-coated silicon wafers which were placed on
top of the bamboo fabric. While the deposition time (ts) for moving substrate was determined
as the duration of time that the substrate spends under the heated filament array, deposition
time for stationary substrate was determined as 60 s. The deposition rates of PHFBA were
given in Figure 3 as a function of substrate speed. According to results, it was found that the
deposition rates observed at different substrate speeds were very close to each other and to
that of stationary substrate within experimental error. This finding is not surprising, because
precursor gas transport velocity is obviously much greater than the substrate speed. It can be
concluded that precursor gas flow profile is not changed according to substrate speed.
Therefore, moving substrate does not cause a significant difference in deposition rates.
However, it must be noted that this observation can be true in under the experimental
conditions applied in this study. Observed trend in deposition rate according to substrate
speed is consistent with the literature that substantiates the idea that deposition rate is
substrate speed independent in roll to roll iCVD process (Gupta and Gleason, 2006).
Figure 3. PHFBA deposition rates on bamboo fabric as a function of the different substrate
speed
In order to evaluate large area contact angle uniformity of PHFBA coated bamboo fabric,
large area bamboo fabric (180 cm in length by 20 cm in width) were coated with substrate
speed of 225 mm/min. After deposition, bamboo fabric was divided into four equal zone,
schematically shown in Figure 4a. The contact angle measurements were performed form
each point at a distance of 20 cm along the length of bamboo fabric in each zone.
During the roll to roll deposition, while one side of substrate surface (frontside) is faced to the
heated filament, the other side of substrate surface (backside) is faced to backside heat
exchanger stage. One of the main advantages of roll to roll iCVD process is the capacity for
polymer thin film coating on both sides of substrate surfaces simultaneously. That’s why,
contact angle results were performed from both sides of bamboo surface. The frontside and
backside contact angle results were given in Figure 4 and Figure 5, respectively. Figure 4
shows static (b), advancing (c), receding (d) and hysteresis (e) of water contact angle of
PHFBA coated bamboo fabric frontside as a function of the longitudinal distance along the
length of substrate. According to the results, all samples from bamboo surface show
superhydrophobic behavior (contact angle>150°). Measured contact angle hysteresis values
can be considered as relatively low, which is a desired property for various applications
including self-cleaning coatings (Men et al., 2016; Shen et al., 2017; Singh et al., 2018).
Figure 4. The coating zone was divided into four different equal areas (a), static (b),
advancing (c), receding (d) water contact angle and water contact angle hysteresis (e) results
of as-deposited film on bamboo fabric frontside at substrate speed of 225 mm/min as a
function of the longitudinal distance along the length of substrate.
Figure 5 shows static (a), advancing (b), receding (c) and hysteresis (d) of water contact angle
of PHFBA coated bamboo fabric backside as a function of the longitudinal distance along the
length of substrate. Backside contact angle values were found very similar to those of
frontside. Both static and dynamic contact angle values are highly dependent on surface
roughness (Gürsoy and Karaman, 2018) and surface chemistry (Gürsoy et al., 2016). The
observed similarities in contact angle results indicate a chemically and morphologically
homogenous polymer film coating in large scale. The small difference in contact angle values
can be attributed to inherent inhomogeneous surface structure of bamboo fabric due to its
fibrous texture.
Figure 5. Static (a), advancing (b), receding (c) water contact angle and water contact angle
hysteresis (d) results of as-deposited film on bamboo fabric backside at substrate speed of 225
mm/min as a function of the longitudinal distance along the length of substrate.
Durability of thin films against environmental disturbances such as laundering is very
important for daily life applications. In this study, the laundering resistance of the fabric was
investigated. After three washing cycle, any significant change was not observed in water
contact angle results.
Furthermore, the wettability of PHFBA coated bamboo was tested against daily liquids other
than the water including milk, coffee, tea, pure apple juice, sour cherry juice and coke. Their
static contact angles (Figure 6 a) and tilting angles (Figure 6 b and Video S1) of all test
liquids were measured as a function of substrate speed. Optical images of uncoated and
PHFBA coated bamboo fabric with were given in Figure 6 c and Figure 6 d, respectively.
When the liquids were dropped on uncoated bamboo fabric, its surface were totally wetted
due to hydrophilic nature of bamboo (Figure 6 c). The liquids droplets were dropped on
PHFBA coated bamboo fabric, all droplets took a spherical shape as a consequence of low
surface energy of PHFBA coated bamboo fabric (Figure 6 d). As seen in Figure 6 a and
Figure 6 b, it was found that changing substrate speed does not influence the wettability
properties of PHFBA thin film. As it is expected that static contact angles were found
inversely proportional to tilting angles. PHFBA thin films deposited with different substrate
speed for each liquid exhibited similar wettability values within experimental errors. On the
other hand, it was observed that obtained wettability values were different from one another
between test liquids. pH differences in liquids can be the most probable reason behind this
observation. It is reported in the literature that changing the pH of test liquid drops placed on
a Teflon surface effected the measured contact angle values (Hamadi et al., 2009). Based on
the results of the study, while the highest contact angle value was obtained at pH 6.5, the
lower contact angle values obtained at lower pH values. Considering the similarity between
PHFBA and Teflon in their chemical structures, the similar results can be expected in our
study. Indeed, in our study, lower contact angle results were measured with more acidic liquid
(fruit juices and coke) as compared to those of water, coffee and tea. Although milk is not as
acidic as fruit juices and coke, the hydrophobicity values of milk was also relatively low on
PHFBA coated bamboo fabric. The reason of that can be attributed to the fat (3.5%) and
phospholipids content in milk (Pan et al., 2019).
Figure 6. Static contact angle (a) and tilting angle (b) of different common liquids on PHFBA
coated bamboo fabric at different substrate speed, Photos of different common liquid droplets
on uncoated bamboo fabric (c) and PHFBA coated bamboo fabric (d).
3.3. Chemical and morphological of Roll-to-roll iCVD of PHFBA thin films
The changes in morphological features of bamboo fabric before and after PHFBA coating
with substrate speed of 225 nm/min were investigated. High (10k X) and low (500 X)
magnification SEM images of uncoated (Figure 7 a and b) and PHFBA coated (Figure 7 c and
d) bamboo fabric were given. According to SEM results, there is no change in the general
appearances of uncoated and PHFBA coated fabric, which indicates a conformal coating of
PHFBA on bamboo fabric. Figure 7 e shows a comparison of FTIR spectrum of roll to roll
iCVD PHFBA thin film to that of HFBA monomer. The peak intensities of both spectra were
normalized at 1760 cm-1 (C=O stretching) (Gürsoy and Karaman, 2016). Both spectra display
the following peak assignments: 1456 cm-1 (CH2 bending vibration) (Gürsoy and Karaman,
2016), 1402 cm-1 (Symmetric -CF3 stretching) (Francisco, 1984), 1288 cm-1 (-CF2 vibration)
(Miller and Hartman, 1967), 1205 cm-1 (-CF stretching) (Zhang et al., 2013), 1112 cm-1 (CF2
stretching vibration)(Zhang et al., 2013), 962 cm-1 (-CF Vibration) (Zhang et al., 2013), 892
cm-1 (Symmetric -CF3 stretching) (Francisco, 1984), 736 cm-1 (-CF deformation vibration)
(Zhang et al., 2013) and 549 cm-1 (-CF3 asymmetric deformation vibration) (Zhang et al.,
2013). iCVD PHFBA thin film does not involve characteristic C=C bond (1633 cm-1) (Gürsoy
and Karaman, 2016) that exists in HFBA monomer spectrum. The absence of this peaks in
PHFBA thin film proves that polymerization occurs through unsaturated C=C double bonds.
Beside FTIR analysis, XPS survey scan was applied to three different points (backside and
frontside) at intervals of one meter along the length of the PHFBA coated bamboo fabric after
roll to roll deposition (Table 1). Based on the XPS results, all points exhibited very similar
atomic percentage for C, O and F elements, these values are very close to the theoretical values
calculated from the chemical structure of the monomer (46.7 at. % C, 13.3 at. % O, 40.0 at. %
F). Similarity in atomic percentage from different points implies chemical uniformity of thin
film coating during roll to roll PHFBA deposition. Moreover, XPS results indicated the
deposition of thin films on both side of the fabric with the similar chemical structures.
Figure 7. Uncoated (a,b) and PHFBA coated (c,d) bamboo fabric, FTIR comparison of
HFBA monomer and PHFBA (e)
Table 1. XPS elemental atomic percentage results of different points on PHFBA coated
bamboo fabric at substrate speed of 225 mm/min
Frontside
Backside
Atomic percentage, %
Point 1
Point 2
Point 3
Point 1
Point 2
Point 3
C
43.8
43.6
44.1
44.0
43.7
43.8
4.
O
12.1
12.3
12.5
12.2
12.3
12.1
F
44.1
44.1
43.4
43.8
44.0
44.1
Conclusions
Roll-to-roll iCVD system allowed superhydrophobic coatings on flexible bamboo substrates
in large scales. The iCVD PHFBA coatings on porous bamboo surfaces were highly
functional, conformal, and uniform. FTIR and XPS analyses showed high retention of
perfluoro alkyl functionality. Large-area contact angle and chemical uniformities were
observed after contact angle and XPS analyses. Depositions were carried out at different roll
speeds up to 225 mm/min., and in each case complete coverage of bamboo surfaces with
PHFBA thin film was observed. A highly hydrophilic material, bamboo fabric, was
completely transformed into a non-wetting material. The roll-to-roll iCVD system developed
in this study can be extended to functionalize many other flexible substrates to impart various
functionalities on their surfaces.
5.
Acknowledgment
This work was supported in part by the Scientific and Technological Research Council of
Turkey (TUBITAK) under the grant program TEYDEB-1507 with project number 7160940.
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Author Contributions Section
Hüseyin Şakalak: Data Curation, Kurtuluş Yılmaz: Data Curation, Dr. Mehmet Gürsoy:
Conceptualization, writing - original draft, writing – review & editing, Prof. Dr. Mustafa
Karaman: Conceptualization, funding acquisition, writing – review & editing.