Questions tagged [polymers]
For questions about synthetic or natural polymers, their chemical or physical properties, and their synthesis, etc.
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Replacing calcium acetate with sodium polyacrylate for homemade Sterno?
I was researching making canned heat using denatured(ethyl) alcohol, water, and calcium acetate from scratch.
However, it occured to me that sodium polyacrylate also absorbs water and alcohol and is ...
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How do you identify which polymers have been formed by radical induced addition polymerization (chain polymerization)? [closed]
Problem:
Which of the following polymers have been formed by radical induced
addition polymerization (chain polymerization)?
Question:
How does one go about solving a problem like this?
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Could polydiazene exist?
I am a bit new to the world of chemistry, and after messing around on ChemSpider, I had a thought. Could a polymer like this exist:
Due to VSEPR, it would be shaped pretty weirdly and N-N single ...
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Is there a name for polymer structures that resemble a foldable lattice?
I'm struggling to find the right descriptors for this, but it would look like this
I've been doing some layperson reading up on stretchy materials, and I know a lot of them work by the polymer chains ...
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Small-Angle X-Ray Scattering of Bulk Polymers
Does anyone have any recommendations on how to get useful information from SAXS of polymers when the system is not dilute?
This is the type of data we're working with:
My understanding is that since ...
3
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Chemical Mechanism Behind Water-Soluble Ink
I came across water-soluble ink pens designed for creating temporary fabric marks, particularly in cross-stitch stamping. These ink dissolve in water, transforming water into a colorful liquid, while ...
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Does polyamide react with hydrocarbons (group III engine oil) in its thermoplastic state?
I need to form (bend) thermoplastic polyamide hose in rubber jacket to a desired shape.
I can use heat gun but I thought for better results I could use heated to 150C group III engine oil (your ...
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liquid (solution or polymer) with a density of more than 1.35g/cm3 and with element atomic numbers less than 9
Search for a liquid (solution or polymer) with a density of more than $\pu{1.35 g/cm3}$ and containing only elements with an atomic number less than 9.
For example, a saturated solution of sugar in ...
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Can multispectral imaging be used for identification of materials, substituting for hyperspectral imaging?
Nowadays a lot of research and applications are using Hyperspectral Imaging for identification and segregation of plastics by material. But the cost of a HSI system is quite high.
Could a ...
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Dependence of elasticity on temperature and degree of vulcanization of typical commercial rubber band
I am doing a school experiment that tries to find how the elasticity of rubber band depends on temperature.
From all the research I have done, theory suggests stress to increase linearly with ...
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How to remove color from bromostyrene/dibromostyrene
Distillation under low heat can remove color (excess bromine) but this is time consuming and there is a danger of bromostyrene polymerization even with added TBC.
In aqueous, sodium thiosulphate can ...
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Can plastic items of same type but different rigidity be recycled together?
Quite often we find plastic items of different rigidity which belong to same type. For instance, LDPE is used mostly for films and bags, but sometimes thick and rigid containers are also made.
Can we (...
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313
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Assignment of NMR peaks of polystyrene
I’m having trouble identifying the peak around 3,75 ppm in the 1H-NMR spectrum of polystyrene measured at 400 Hz in CDCl3. Could someone please provide their perspective on it? I see it appear in a ...
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1
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Does Sugru (Formerol) decay underwater?
Sugru is described as waterproof and dishwasher-safe, but I still wonder if it will decay quickly (within months) if submerged in room-temperature tap water.
Aren't silicone rubbers susceptible to ...
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Which is more stable, a secondary allylic carbanion or a primary allylic carbanion?
I came across this picture in a polymer chemistry course, specifically on anionic polymerization of conjugated dienes (butadiene).
I dont understand why the secondary carbanion is more stable. Based ...
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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 ...
2
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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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1
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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 ...
3
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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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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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1
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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 ...