Moisture absorption experiment of activated carbon felt results show less absorption weight than PDMS coated ACF why?

Chandrika Ashwinikumar Pal @Chandrika-Pal

11 September 2023 1 6K Report

I am doing humidity moisture experiments in which I'm using the bare ACF and the PDMS-coated ACF after the experiment I can see that the weight (mass) changes of the material are higher in the case of PDMS-coated ACF than the bare ACF. I cannot understand why it is happening. Is it because of the hydrophobicity of PDMS or moisture in the water vapor form is getting trapped in the felt? Please help me to understand this

Gaurav H Tandon

The results of your moisture absorption experiment, where activated carbon felt (ACF) showed less absorption weight than ACF coated with polydimethylsiloxane (PDMS), can be explained by several factors related to the properties of these materials and the experimental conditions.

Here are some possible reasons for the observed difference in moisture absorption:

Hydrophobicity of PDMS: PDMS is a hydrophobic material, meaning it repels water and is less likely to absorb moisture compared to many other materials. When ACF is coated with PDMS, it becomes less porous and less capable of absorbing moisture, as the PDMS layer forms a barrier against water penetration.

Coating Thickness: The thickness of the PDMS coating on the ACF can significantly affect moisture absorption. If the PDMS coating is relatively thick, it can further reduce the ACF's ability to absorb moisture because it creates a more effective moisture barrier. Thin PDMS coatings may still allow some moisture absorption by the underlying ACF.

Experimental Conditions: The conditions of the moisture absorption experiment can also impact the results. Factors such as temperature, humidity, and exposure time can influence the rate and extent of moisture absorption. If the conditions were more favorable for moisture evaporation or if the experiment was conducted for a shorter duration, it could result in less moisture being absorbed.

Porosity and Surface Area: Activated carbon felt typically has a high surface area and porosity, which can enhance moisture absorption. However, when coated with PDMS, the available surface area and porosity may be reduced, limiting the ACF's ability to capture moisture.

Surface Energy: The surface energy of materials can affect their interactions with water. Hydrophobic materials like PDMS have low surface energy and are less likely to interact with water molecules through hydrogen bonding or other attractive forces, making them less effective at moisture absorption compared to hydrophilic materials.

Moisture Source: The source of moisture in the experiment could also influence the results. Different moisture sources may have varying levels of humidity and water vapor pressure, affecting the rate and extent of moisture absorption by the materials.

In summary, the difference in moisture absorption between activated carbon felt and PDMS-coated ACF can be attributed to the inherent properties of these materials, including their hydrophobicity, porosity, and surface energy, as well as the experimental conditions and the thickness of the PDMS coating. PDMS's hydrophobic nature and its ability to act as a moisture barrier are likely key factors in reducing moisture absorption when it is coated onto ACF.

Badges
Science topic

More Chandrika Ashwinikumar Pal's questions See All

Why is the sum of the elements in a row in a Q matrix equal to zero?

When explaining substitution models, the substitutions are expressed as Q matrix. Why is the sum of the elements in a row zero?

28 February 2021 3,864 3 View

Desalting using DSC- 18 SPE columns?

I am looking forward to remove excess of salt form my metal based porphyrin and trying DSC-18 columns for the same, can someone suggest me how how can one decide the polarity of the solvent to...

01 February 2021 9,076 1 View

Can we use two antibodies generated in same species for indirect Sandwich ELISA?

I have generated two antibodies against two peptide fractions of a protein in the rabbit. I want to use these two antibodies (Ab-1 and Ab-2) in indirect sandwich ELISA for the detection of...

11 January 2021 1,754 4 View

I want to quantify disturbance for wetland birds?

I have categorized the disturbance basically on movement of people and vehicle in into 3 categories. Disturbed, close to highway and movement of people from dusk to dawn. Intermediately...

30 December 2020 8,806 4 View

I am amplifying my target region through PCR, but I am getting number of unwanted band also with my target region...Why?

I have checked annealing temperature through gradient PCR. I have checked my primer in NCBI. I have checked PCR reagents concentration. Please suggest me anyone thanks

12 December 2020 1,969 2 View

What is the relationship between the type of material(ex: steel, iron etc.), thrust and torque?

If I am drilling through bars of different material(ex: iron, steel etc.) of the same thickness and under the same conditions of drill operations(feed rate and rpm), how will the torque and thrust...

06 November 2020 4,498 3 View

How to coat plasma sample (Antigen) in ELISA plate for a direct ELISA?

I have generated an antibody against an antigen. Now, I want to use the developed antibody in the detection of the unknown sample. So, I want to coat the plasma sample as antigen. How that can be...

26 October 2020 2,259 7 View

How the geospatial variability in the heat requirements of crop due to rising temperatures analyzed?

As we know that the global temperatures are increasing due to climate change which could affect the thermal needs of the crops. I want to make geospatial maps and analysis for heat requirements of...

28 September 2020 8,286 2 View

Some issues regarding electrical simulation of a Nanoowire based MSM Photodetector using Synopsys Sentaurus TCAD ?

I am simulating a NW based MSM Photodetector with Si/ CdTe/InAs NWs (modeled in SDE)with moderate doping, and have assumed a constant generation rate in the the Physics Section of SDEVICE 1....

03 September 2020 5,971 10 View

Can any body suggest the funding agency for Research Project on climate change and Remote Sensing?

I tried to submit research projects on climate change and Remote sensing to many agencies but could not get it though? Is there any easily available agencies who support the research in the subject.

16 August 2020 4,000 18 View

Which is suitable for use with Python? MySQL or SQL Server?

Which is suitable for use with Python? MySQL or SQL Server? What is your suggestion?

01 March 2021 3,422 3 View

How to separate water from glycerol solvent in a solvent recovery vacuum distillation column?

I am currently doing my third year design project. I have been assigned to design a glycerol recovery column in vinyl acetate monomer production. The process unit before the recovery column is an...

01 March 2021 9,525 4 View

What is the state of the drug inside solid lipid nanoparticles (SLNs)?

I am a little confuse with the mechanism of solid lipid nanoparticles (SLNs). The main point of encapsulating drugs into SLNs is because some drugs have low solubility in water. Therefore, SLNs...

01 March 2021 3,703 3 View

How to check the uv-vis absorption of nanoparticle by surface plasmon resonance?

I try to check the uv-vis absorption of Indium nanoparticle. Now I am measuring in solution, can I measure it in the form of a film?

01 March 2021 930 3 View

How to remove the residual PDMS on the silicon mold?

Incompletely cross-linked pdms are difficult to remove.

01 March 2021 798 3 View

Why is the sum of the elements in a row in a Q matrix equal to zero?

When explaining substitution models, the substitutions are expressed as Q matrix. Why is the sum of the elements in a row zero?

28 February 2021 3,864 3 View

Does different dilution factors affect negatively on NH3 reading ?

I have a sample of treated water sample & asked to obtain ammonia conc. in sample using a machine with 5-25 ppm detection range. However, upon testing with different dilution factors, all...

27 February 2021 8,483 3 View

Why initial concentration of Pb not the same as calculated one when testing using AAS?

I am currently doing research on the adsorption of heavy metal using magnetic reduce graphene oxide. I use AAS to determine the concentration of the heavy metal. I prepare the Pb solution with...

26 February 2021 9,580 4 View

LEDs on Vis Light photo degradation of MB water sol via N doped TiO2 in a mini flume?

Good day to all, I have no experience with light emitting diodes. I am building a glass mini flume to demonstrate the photo degradation of Methylene Blue in water running over self cleaning...

26 February 2021 4,026 5 View

What are the saturated salt solutions that can give specific relative humidity of 35%, 65% and 95% for conditioning wood specimens?

Due to the unavailability of climate rooms, I want to carry out an experiment that require the use of certain saturated salt solutions especially those that can condition the wood specimen to 35%,...

25 February 2021 8,139 1 View