Questions tagged [polymers]
For questions about synthetic or natural polymers, their chemical or physical properties, and their synthesis, etc.
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Isotope composition effect in Fullerene/Buckyball stability [closed]
Consider the relationship between eagle eggs and DDT, where a slight thinning in the eggs made the egg's structural stability non-linearly weaker.
Now, consider 1 fullerene (buckyball) made entirely ...
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Thermoplastics crystallization during nonisothermal cooling cycles
I have tested a PAEK family polymer using differential scanning calorimetry (DSC) with heating-cooling-heating cycles under different cooling rates (heating rates remained unchanged). PAEK are semi-...
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Can polychloroprene further react
Chloroprene undergoes radical polymerisation to form polychloroprene.
Chloroprene is a special structure since it has two carbon-carbon double bonds and it turns out that polychloroprene also has one ...
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cellophane bags
I am conducting an experiment to test the components of a cello bag. I believe that cello bags do not just contain cellulose, and as mentioned by many websites, only 92-98%, but not 100% of the bag is ...
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How to dissolve paraformaldehyde in solvent without using water?
In the chloromethylation reaction of polysulfone (PSU), I am required to use paraformaldehyde and trimethylchlorosilane as the chloromethylating agent while stannic chloride as the catalyst. I ...
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Adding colours to polymers
It is said that some polymers can be dyed, but I am not sure about the mechanism behind.
Let me take an example. In anodization, aluminium oxide can be coloured since there are tiny pores for the ink ...
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Why does ethanol decrease viscosity of a high pH carbomer solution more compared to water
Carbomer 407 is made up of acrylic acid that undergoes polymerisation to form a long linear structure. At higher pH, the carboxylic acid functional groups will dissociate to form carboxylate ions. ...
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What resin is appropriate for construction of a gasoline/ethanol fuel tank
I am building a epoxy resin/glass reinforced plastic (epoxy/GRP) gasoline tank. The expected service life is 30 years.
I've read that epoxy is relatively resistant to gasoline (some better than others)...
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What is that substance coming from tractor tire?
I have old tractor with Bridgestone tires. When I press a clean white tissue against the tire, a black spot show on the tissue. Is that substance carbon black and it’s harmful to soil?
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What is the diffusivity of colloidal Formazine in water?
I have synthesized Foramzine in an aqueous solution (turbidity = 4000 NTU), and will be further diluting it. I would like to know the diffusion coefficient (diffusivity/mass diffusivity) of colloidal ...
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Is the "heat or UV" necessary for PVC10 + Cl => CPVC10 catalytic or endothermic and if endothermic how much energy?
Production of Chlorinated PolyVinyl Chloride (CPVC) from PVC and chlorine requires incorporating about one part chlorine in 10 PCV to achieve around 63% chlorine mass CPVC. This reaction is "...
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Why is sodium p-toluenesulfonate used as a supporting electrolyte in polypyrrole synthesis?
First, some preamble: I'm currently working on my thesis, which is about the electropolymerization of polypyrrole onto carbon fiber felt. My methodology, for the most part, follows a paper by one of ...
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Can an epoxy resin create a terpene polymer?
I am developing plant-based antifouling coatings that will stop barnacles binding to ship hulls for example. I have started simply by mixing specific terpenes with an epoxy resin (BISPHENOL A ...
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Acetone resistant elastomer
I am in search of an elastomer that can be dissolved in solution and applied and cured at room temperature, but that has good chemical stability to acetone once cured. Does any such elastomer exist?
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How do polyurethane varnishes cure after only the solvent evaporates
How do polyurethane varnishes cure after only the solvent evaporates?
I believe that polyurethane varnishes have as components isocyanates & polyols that react to form the polyurethane portion of ...
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How can I compare the UV/Vis absorption difference after metal ion chelating of crown ether-containing polymer?
Recently I have synthesized the polymer that contains 1-aza-18-crown-6 in the repeating unit. I want to know if there is any UV/Vis absorption difference after the chelation of metal ion. Considered ...
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Effect of changing of the concentration of reactants when concentration of the initiator and the concentration of the initial reactant are very small
A + I---> p
What happens to the rate of the reaction when the concentration of the reactant is changed in a system that its concentration of its initiator and the concentration of the initial ...
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Would a "chain" of ring polymers be possible?
Basically what the title asks. By a "chain", I mean a structure where you have two or more ring polymers (polymers where the ends are joined to form a large circular/ring-shaped molecule; ...
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Oxygen tolerant RAFT polymerization using AIBN?
I want to do some RAFT polymerizations but don't have a nitrogen line at the moment. It seems that people have recently implemented oxygen scavenging strategies to enable open-air RAFT polymerization. ...
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Choice of nonsolvent in polymer purification by reprecipitation
Recently, I have synthesized new polymer. To purify the polymer, I tried reprecipitation. Because general nonsolvent is methanol, I dissolved the polymer in dichloromethane and reprecipitated into ...
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Derivation of Flory's Model for Linear Condensation of Polymers
I'm having some trouble understanding a part of Flory's model for linear polycondensation reactions. In his 1936 paper, he derives an expression for the probability of the existence of a particular $x$...
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What two processes occur that dictate the microstructure of a polymer?
Firstly, I'm not 100% sure on what a microstructure is as our lecturer didn't explain it all too well. From what I've gathered, its the backbone structure of the polymer chain - but I may be wrong.
In ...
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Why can i not use glue (which contains cyklohexane, petrol and ethyl acetate) for gluing PVC materials? [closed]
The manufacturer do not recommend using glue to gluing PVC. But Why? Thank you for your help.
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Is there any literature regarding the neutral hydrolysis of nylon 66?
I am working on a project for my thesis regarding the neutral hydrolysis of nylon 66 at high temperatures and pressures (265C,40 bar) however the only literature I could find relates to alkaline and ...
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Will ethyl 2-amino-1H-imidazole-5-carboxylate undergo ester aminlysos with the primary amines of bPEI efficiently in methanol?
I was about to set up the following reaction, but before I do, I wanted to see if anyone has some suggestions or thinks this will not work:
24mmol Nboc protected ethyl 2-amino-1H-imidazole-5-...
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Could you tell me the name of this compound please? [closed]
Could you please tell me make of this compound?
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At the atomic or molecular level, why are some macroscopic materials more flexible, compared to others?
Before answering this question, keep in mind that I am a 2 year Biology student, with limited experience in studying chemistry. I am going to make assumptions which I explain, feel free to correct ...
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How does the branched structure of glycogen, increase its ability to be hydrolysed?
"Glycogen branching is essential because it allows for increased water solubility and several sites to break it down; this allows for easy and quick glycogen utilization when it is broken down&...
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Cause and Prevention of Palladium Mirror in Stille Coupling
I am conducting some monomer and polymer syntheses using Stille coupling or other palladium-based coupling. I usually use the combination of $\ce{Pd_2(dba)_3}$ and $\ce{P(o-tol)_3}$ in Stille coupling,...
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Why are certain hot polycarbonate films stickier than others? Molecular weight? Hydrolysis?
In van der waals dry transfer, we pick up flakes of materials such as graphene using polymer films. The material is exfoliated onto an SiO2 covered wafer and picked off using the polymer film. It's ...
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Do NaHCO3 and cyanoacrylate react? [closed]
I just saw this video about using baking soda + cyanoacrylate(CA) glue as a substrate+resin.
Neat, but do CA and $\ce{NaHCO3}$ react in any way?
If so, what does the equation look like and what is ...
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How to estimate the mobility constant and the surface energy parameter in the Cahn-Hilliard equation?
As a mathematician, I want to simulate phase separations with the Cahn-Hilliard equation
$$
\frac{\partial c}{\partial t} = M \Delta \bigg(\frac{\partial \mu}{\partial c} - \kappa \Delta c \bigg),
$$
...
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Detecting epoxy in a polyester powder coat paint
I have 2 steel parts which were both powder coated in a polyester powder coat, however one of them does not perform exactly as I would expect it in my unusual use case which depends on temperature. I ...
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What is the number of Gaussian chains of network per unit volume of rubber?
In this chapter, page 70, I encountered the term `Gaussian chains of network'. In equation 3.34 (page 73) of this chapter, the phrase 'n is the number of moles of Gaussian chains' occurs in the ...
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How to add any polymer to azobenzene?
I want to make a polymer by adding two polymeric substituent groups to azobenzene (I would like only N-azobenzene-N where N is a polymer and repeats). I have been reading about how they make the ...
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Is there really no solvent (or any other really) glue for polyethylene terephthalate?
PVC can be glued well with solvent cement wherein it melts somewhat and then sticks together really well as if it was welded, which is really convenient. But I can't find anything similar online for ...
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1,1-Diphenylethylene subproduct/impurity
I'm working with 1,1-diphenylethylene and I've observed that, if left at room temperature in the air atmosphere, a white insoluble powder forms. I'm unable so dissolve this powder in every solvent ...
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Does acrylic resin in acetone react with the same acrylic resin in ethyl acetate?
I am not at all familiar with organic chemistry. I am working in museum conservation where an acrylic resin (such as Paraloid B-72) is mixed acetone and sometimes ethyl acetate to produce a resin for ...
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Polymer purification by reprecipitation troubleshooting
I am synthesizing new polymer that has not been reported before. The structure of the polymer is based on indacenodithienothiophene unit and thiophene. I used Stille polymerization. As monomers, I ...
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Is polycarbonate resistant to extremely cold temperatures?
I am working on a project which involves the use of polycarbonate. Polycarbonate is quite a new material to me as I haven't worked with it yet. I want to know its characteristics in detail, as it ...
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creating hydrogenated castor oil/sebacic acid copolymer [closed]
I would like to create a copolymer using Hydrogenated castor oil and Sebacic acid to create a hair conditioning treatment, however I dont know where to begin so any advice will be highly appreciated.
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What material(s) can offer similar performance to polyurethane in a paint coating, but with less hydrogen?
We need to coat parts of an neutron instrument with a boron shielding coating. This currently is achieved using an airbrush gun with a paint mix of demineralized water, polyurethane and boron powder.
...
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Recovery of precipitated polymer
I have recently newly synthesized the polymer. Based on its structure I tried to precipitate its concentrated solution in dichloromethane by dropping it into methanol. It seemed to work. The methanol ...
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How to increase basis set while running cluster calculations
I am running (opt+freq)DFT calculations using 6-311G(d) basis set on polymers with different number of monomer units. Upto 2 monomer units optimization is converged but for 4 units max displacement ...
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In bulletproof vests, why do we use ceramic plates instead of metal?
In many articles, it has been mentioned that bulletproof vests also contain ceramic plates for extra protection. Wouldn't it be better to use metal instead? Since ceramic breaks easily.
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Can flaxseed (linseed) oil undergo hydrogenation?
I'm curious if it's possible to chemically hydrogenate flaxseed (linseed) oil. I've never seen it in hydrogenated form. Given its quality as an excellent wood protectant, I figure it would be easier ...
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how to make a PEM (proton exchange membrane) out of Nafion Dispersions?
I would like to use a Nafion membrane for a fuel cell project, but the Nafion sheets are hard to integrate. Therefore, I would like a gel type of Nafion that can take the shape of the container I put ...
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Best material selection for a component containing hot saturated-level saline water with high chloride content (Polymer vs coated metal)
I have a component (Which can be seen as the attached file)
and inside the component, there would be hot saturated-level saline water with high chloride content (Not shown)
Considerations:
The ...
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Vinylic Nucleophilic Substitution [closed]
While reading "Francis A. Carey, Richard J. Sundberg - Advanced Organic Chemistry Part A. Structure and Mechanisms-Springer (2007)", I came across the following schematic for addition of ...
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Why is the rubber tip of my capacitive stylus no longer conductive?
In 2014, so eight years ago, I bought five styluses from China. Cheap stuff obviously. They worked fine while I used them, but soon after they were just left in a drawer. Last night I realized that ...
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