About Me:
My Name is Steph Korunow and I am a Chemistry Teacher at South High Community School in Worcester. I originally came to Worcester to study chemistry and art history at Clark University. When I graduated in 2012 I started the Master of Arts in Teaching Program at Clark University while student teaching at South High Community School. I have been teaching Chemistry at South High for the past 12 years! I have primarily taught Introduction to Chemistry courses but recently have taken over the AP Chemistry classes at South High. I also run the LGBTQIA+ Club at South High giving students a safe space to be themselves!
Outside of the classroom you will find me reading a sci-fi book, learning a new craft or recipe, playing TTRPGs and spending time with my many pets!
About the Lab:
The Grimmgroup focuses on surface science with collaborations in Civil Engineering to understand the science behind concrete strength as well as ways to improve sustainability, longevity, and durability.
Concrete is one of the most common building materials in the modern world; however, after time and strain mechanical defects can occur leading to impaired strength and resilience. These defects are normally present at the interface between aggregate–such as sand–and Portland cement paste. In order to improve the cohesion between the aggregate we are examining chemical modification to the aggregate surface. As sand is a silicon-oxide surface, silanes will allow us to functionalize the surface with a variety of chemical functional groups. During this project we will use glass slides, another silicon-oxide surface in place of sand as glass allows us to more easily employ spectroscopic techniques.
Herein, we will use silanes to change the chemical interface between glass slides (that serve as a proxy for aggregate surfaces) and thin films of calcium silicate hydrates and oxides. Calcium silicate hydrate (CSH) is the matrix that gives concrete its primary strength. Early research indicates that certain silanes, specifically (3-glycidoxypropyl)trimethoxysilane (GPTMS) interact favorably with the CSH network. We will investigate the interactions of GPTMS and other silanes with the naturally forming CSH in concrete.
We are going to derivatize glass slides with 3-glycidoxypropyl)trimethoxysilane (GPTMS), 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 8-glycidoxyoctyltrimethoxysilane, and aminopropyltrimethoxysilane. We will deposit calcium via calcium hydroxide solution. The hydroxide allows for ring-opening on the epoxide group allowing for calcium ligation. Infrared spectroscopy will characterize silane attachment and changes in silane due to interaction with CSH. X-ray photoelectron spectroscopy will establish the ratio of calcium and silicon in the CSH layer produced on the surface of the aggregate. X-ray diffraction will allow us to observe the crystal structure of these CSH films and whether silane-functionalization changes those structures.
Time permitting we will further explore changes to spectra when zinc(cyclen) is introduced to the various silane surfaces. One functionality is the ability to covalently tether a molecular mimic for the enzyme carbonic anhydrase, called zinc(cyclen). This catalyst allows for the formation of carbonate ions (CO3-2) from environmental CO2, which in a calcium-rich environment will precipitate calcium carbonate plainly called limestone.
UN Sustainable Development Goals Alignment:
The Grimmgroup research with silane-functionalized concrete can be used toward reaching Goal 11 of the UN Sustainable Development goals, specifically 11.3 and 11.c (see below). Concrete is a very common building material used throughout history but it also produces high amounts of CO2 into the atmosphere. The Grimmgroup is currently working on exploration of concrete that is more sustainable, long lasting and could remove carbon dioxide from the air. Currently we will be exploring silane-functionalized concrete. This concrete has been found to be stronger under compression tests than other concrete. The research laid out above would help move the lab group forward toward the development and understanding of more sustainable and long lasting concrete that can be used in urban development. This would allow for public works to last longer, be safer and require less maintenance while also being less harmful to our environment.
UN Sustainable Development Goal 11: Sustainable Cities and Communities
11.3: By 2030, enhance inclusive and sustainable urbanization and capacity for participatory, integrated and sustainable human settlement planning and management in all countries
11.c: Support least developed countries, including through financial and technical assistance, in building sustainable and resilient buildings utilizing local materials
Project Title:
Investigating Early Strength in Silane-Functionalized Concrete through Surface Science: An Exploration of Calcium Silicate Hydrate Spectroscopy
Weekly Updates:
Week 1: (6/27/24 – 7/03/24)
I started off the first week going through onboarding to the RET program as well as meeting with the members of the Grimmgroup Lab. This first week I worked closely with Ally, the pre-practicum teacher I have been paired with. Ally showed me around the lab and how to complete common procedures used by the Grimmgroup. We went over how to make piranha solution which is used to clean organics off of the glass slides and sand we will be using. She also showed me how to use the glove box and flush box which are used to keep a dry and air free environment. Lastly we silanized some of our slides with GPTMS to prep for further investigation. By the end of the week we met with our mentor and graduate student to narrow down our project. I was then trained in how to use the IR Spectrometer so that we could run slide samples throughout the summer.
Week 2: (7/08/24 – 7/12/24)
This week I took background IR on the piranha cleaned slides from the week prior. With thisbackground we hope to subtract that spectra from our silanized slides so we can detect peaks causes from the silane structure binding with the SiO2. After running IR on these slides we found that the peaks did not have enough definition or clarity to be useful for our research. We also had an issue with the XPS so we are unable to use that for at least a week. This lead to another meeting with Grimm to determine what to work on going forward. From here we decided to focus on analysis we can do with the equipment available. I will be working on preparing samples of sand that have been piranha cleaned and then silanized with various different silanes. These will be sent to Civil Eng. to be used to make concrete samples that can be tested for strength. I will also be working closely with Ally to find a column chromatography technique that would allow for the purifications of crude Zn(cyclen).
Week 3: (7/15/24 – 7/19/24)
This week I worked on preparing silanized sand samples. These samples will be sent to the civil engineering department to be used to prepare concrete samples. These samples will be allowed to cure for 14 days and 28 days before being tested for compressive strength. The first thing I needed to do to prepare these sand samples was to piranha Clean the sand. piranha solution contains 3 parts concentrated sulfuric acid and 1 part 30% Hydrogen peroxide. This solution eats away all organic materials on the sand leaving a clean Silicon dioxide surface. The solution is rather dangerous and must be contained in the hood while being used and can even eat through nitrile gloves. Once the Sand is cleaned it then must be neutralized with DI water. Finally the sand is dried on a roto-vap before being silanized. To silanize the sand we must keep the silanes in dry environment. Using a flush box, a box with nitrogen pumped in to prevent water and oxygen from interacting with the materials inside, we measured out our chosen silanes and solvents. The mixture of silane and solvent is placed over the sand and it is allowed to sonicate for several hours to allow for the silane to attach to the surface of the sand. After these four hours the sand is washed and dried on the rotovap and packaged up for Civil engendering.
For the silanization we chose four different silanes with varying structures. For most tests we use GPTMS which is a silane with an epoxy ring at the end of the chain. This silane is cheap so it is a good choice for general tests. When tests were done on the concrete strength it was found that GPTMS treated sand gave similar strength to dirty sand after 14 days. This lead to a discussion on why this silanized treated sand has increased strength even without the addition of Zn(Cyclen). To further explore this the 4 silanes have different structures. Two of the structures also had epoxide rings, one with a longer chain of carbons than GPTMS and one with a carbon ring with the epoxide built on it. We wanted to vary the structures while still having the epoxide ring to see if it is playing a roll in strength. We also picked a silane with a phenyl group, this group is very hydrophobic and would act similar to “dirty” sand. Lastly we picked a sample with amine groups to explore if any nitrogen deposition on the surface may be effecting strength.
Week 4: (7/22/24 – 7/26/24)
This week was focused on trying to finalize as much of our sample prep so that we could hopefully get data back in time for the final poster due dates. I stared the week in the civil engineering lab. Becca and I met with Dalton to plan out what our next steps were for producing the concrete samples that we need to get our early strength data. Dalton spent time sieving sand for me while Becca and I met with Mobin to run SEM scans of some of the concrete samples that have already been cured. SEM (Scanning Electron Microscopy) allows for us to take a look at the surface and structure of the concrete at a 1-10 micron level. We took a look at concrete that had made with dirty sand and with Zn(Cyclen) Tethered GPTMS sand.
I then spent the rest of the week working of preparing our samples. First I piranha cleaned and dried a lot of fine grain sand. From there I bound GPTMS to Zn(Cyclen). This process must be done in an air free environment. To manage this the solution is prepared in a glove box. The glove box pumps out air and pumps in nitrogen to allow for water and oxygen to stay out of the environment. From their the reaction was run on the schlenk line to allow argon to be run into the flask. While the reaction is set up it is help under active argon allowing for a constant flow and pushing out any air that may come in. It is left overnight to react under passive argon where the flask has been filled with argon gas and sealed. The next day I used the solution to silanize the sand I had treated. I silanized one sample of piranha cleaned sand and one sample of dirty sand to compare. These samples were sent to Dalton at Civil Engineering to be turned in to concrete cubes for early strength tests after 1, 3, 5 and 7 Days.
Week 5: (7/29/24 – 8/02/24)
This week was focused in on writing and revising the rough draft of my poster. During the week I got feedback from my mentor professor Ron Grimm as well as from the RET group. The other focus of the week was meeting with Donna and doing PD on my lesson plans and trying to connect it back to the standards as well as the UN sustainable goals. Finally I attended the REU Poster session, it was really wonderful getting to see the posters of the undergraduates who also worked in the Grimm Lab. It also gave me a little idea of what our poster session would look like next week. During this week Dalton in Civil engineering worked on making my sand into concrete samples. Hopefully I will get some data back on the compressive strength next week!
Week 6: (8/05/24 – 8/09/24)
This was the last week of the program! This week was spent getting ready for our poster session and wrapping up anything left to do! During the week I visited other RET participants labs and got to see a little bit more about what they did through the summer! We also went on a field trip to Coe’s Pond to get to know more about the water testing in Worcester and how they test for cyanobacterias! We closed out the week with our Poster Presentation!
Final Poster:
Stephanie_Korunow_RET_Poster_FInal
Lesson Plan: Coming Soon!