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Questions tagged [polymers]

For questions about synthetic or natural polymers, their chemical or physical properties, and their synthesis, etc.

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Will lead bind to dissolved polymer (Kapton) monomers?

We are attempting to determine the concentration of lead impurities in Kapton. Essentially we need to extract lead in the tape polymer Kapton (structure seen below); The amount of lead in the tape is ...
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What is the difference between radii of Gyration and hydrodynamic radii of a polymer? [closed]

Why do you consider that the relationship between RH and RG should depend on the quality of the solvent?
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57 views

Is it possible to arrest the post-actinic effects of photodegradation in ABS polymers?

Polymers like ABS are adversely effected by UV exposure, both visually (by yellowing) and with regard to other material properties [1]. What's worse is that the degradation of the material continues ...
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1answer
44 views

Does melting HDPE plastic produce toxic fumes? (melting, not burning)

● The question isn't about burning HDPE but melting it at the proper temperature. (At 120 to 180°C depending on it's density, it becomes gooey. According to the source below the "extrusion" ...
3
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1answer
234 views

What would happen if I combined this polymer and this metal (assuming I can) [closed]

So let me explain, I recently found out about a material called sorbothane (which is a polymer). Now, sorbothane is special because not only does it highly efficiently absorb shock, but also highly ...
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2answers
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Why isn't nylon as strong as kevlar?

Why is Kevlar stronger than nylon? They both contain Hydrogen bonding and should have equal strength but this is not the case instead Kevlar is fire resistant. What makes it stronger. Greater hydrogen ...
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0answers
23 views

Which Flocculant/Coagulant is ideal for harvesting Algae?

While dealing with Algae fit for human consumption (as protein supplements), which is the most suitable coagulant/Flocculant available? Factors to consider: 1) Cost Effectiveness (for instance poly ...
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1answer
28 views

What does the slash in polymer nomenclature, e.g. Acrylates/ Beheneth-25 Methacrylate Copolymer, mean?

I was given a task to find SDS-Sheets for polymers/microplastic particles in cosmetics and I am confused, since there are often two chemicals divided by "/", e.g. Acrylates/ Beheneth-25 Methacrylate ...
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Can amorphous polymers have a melting temperature as well as their glass transition transition temperature?

Above the Tg, amorphous polymers are described as viscous liquids. What then would they be likened to above their melting point, should they have one?
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31 views

Why can't a thermosetting plastic be stretched like an elastomer?

So far I've learnt that there are 2 'types' of thermosets: thermosetting plastics and thermosetting elastomers. Both of them consists of crosslinks that when stretched, allows for the material to ...
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0answers
20 views

what is the material used to detect the presence of free radicals in the reaction?

To detect the presence of free radicals in the reaction usually, acrylonitrile used but this material is not available in my university. Is there another material used to detect the presence of free ...
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29 views

explanation of why interphase occurs in polymers

Im new to chemistry network of stackexchange so please be kind to me! I heard that interphase is created in clay polymer for 2 reasons. one of the reasons is the insoluble part of the polymer and the ...
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1answer
28 views

Is temperature of crystallisation same as melting point temperature for polymers?

Melting point tends to be a temperature range. Is it true that the temperature of crystallisation is the highest temperature at which the polymer melts and thus there is some distinction between ...
7
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1answer
55 views

Why isn’t there LDPP, HDPP?

Unlike polyethylene that there are LDPE, HDPE, or LLDPE, when it comes to polypropylene the issue becomes about copolymer (homo/ copo/ block copolymer) or location of methyl group (isotactic/ atactic/ ...
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2answers
147 views

Finding the repeating unit of polymerisation given two constituent molecules

The compounds $\ce{H2NCH2CH2NH2}$ and $\ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer? A. $\require{enclose}\ce{\enclose{horizontalstrike}{(}...
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129 views

Does propylene glycol dissolve plastic?

According to Médecins Sans Frontières propylene glycol can dissolve plastic: As propylene glycol can dissolve plastic... (Source). Is this claim true? This seems rather spurious to me. If it ...
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0answers
15 views

Why does the degree of polymerisation remain the same throughout chain-growth polymerisation?

It is known that the degree of polymerisation, which is the average number of monomer units in each polymer chain formed, increases as the reaction proceeds for step-growth polymerisation as longer ...
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0answers
32 views

Polymer that has aldehyde and carboxylic acid functional group

I'm currently identifying an unknown polymer sample and I found out from raman spectroscopy that it may contain aldehyde and carboxylic acid functional groups (and possibly ketone too). I was looking ...
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1answer
295 views

Do all polymers contain either carbon or silicon?

Is either carbon or silicon present in every known polymer? If not, is there a small group of elements that, between them, are present in every known polymer, or can polymers be based on a lot of ...
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1answer
19 views

Polyethylene terephtalate Biodegradability [closed]

I'm looking into plastics and how they break down. I have learned 3 ways oxo-biodegradation, photodegradation and thermaldegradation. Does anyone know how PET (polyethylene terephtalate) degrades?
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7 views

Can any body Suggest me a set up that I can build it up to study the surface roughness of transparent polymeric fibres?

I need to study the surface of nylon-6 blank fibres with a thickness of nearly 40 micrometre, I work in optics lab with many optical components such as beam splitters, lenses, mirrors ... etc, can I ...
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0answers
27 views

Where can I look for a short chain photopolymer?

I am by no means an expert in this field, so please be patient with my explanation. I am looking for a photopolymer with very specific properties. I am not sure how realistic it is to find such a ...
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1answer
33 views

Spraying aluminium hydroxide nanoparticles onto PLA as fire retardant?

Several scientific papers study FR-PLA (fire resistant PLA) in which Aluminium Hydroxide nanoparticles are melt blended into the PLA (example source: Advances in Flame Retardant Poly(Lactic Acid). ...
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1answer
44 views

diamine synthesis

I want to synthesize a new polyimide based on new diamine. In the first step of the synthesis of this diamine, my monomer was added to mixture of 1-chloro-4-nitrobenzene and potassium carbonate in ...
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1answer
21 views

Hardened polyurethane remover

I've looked at the MSDS of a couple of products for removing hardened polyurethane (PU) foam. Both contained only ethanolamine as a dangerous substance, but only between 1-5%. So I'm guessing this ...
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1answer
46 views

Mixing of molecular orbitals in polyatomic molecules

I am trying to solve the following Hamiltonian,$$H=-\frac{1}{2}\nabla^{2}-\sum_{i=1}^{10}\frac{1}{|\vec{r}-\vec{R_{i}}|}$$ Here $Z=1$ . To get all ther molecular orbitals of this system. I took the ...
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1answer
30 views

Some information about DOWXV503 [closed]

I want to know about the attractor DOWXV503. Is there any scientific book or article about this material? Any information is useful and it will be appreciated.
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1answer
720 views

Can a long polymer chain interact with itself via van der Waals forces?

It is known that van der Waals interaction is an intermolecular forces. So is it possible that a long polymer chain interacting with itself via non-bonded interactions (such as van der Waals forces / ...
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1answer
29 views

How can I prevent my spin-coated silica thin film from cracking when I heat it up?

I am spin-coating a porous silica solution on a glass microscope coverslip, and then heating the resulting thin film to $\pu{350 °C}$, in an attempt to create a thin film of porous silica sol gel. I ...
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1answer
43 views

Molecular Orbital Mixing to get the Molecular Orbitals of a large molecule

I am trying to get the molecular orbital for arbitrarily placed nuclear centres (identical). In other words , I am trying to solve the following one electron hamiltonian. $$h=-\dfrac{1}{2}\nabla^{2}-\...
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1answer
54 views

In search of a safe and inexpensive solvent that can dissolve depolymerized polypropylene waste plastic

I work at a place where we depolymerize post consumer waste polypropylene waste plastic through a thermal catalytic conversion process. During process shutdown we have to clear up the vessels which ...
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0answers
18 views

Are linear alkanes polymers? [duplicate]

Let me ask a basic question. Wikipedia defines a polymer as A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Now, can we think of a large linear alkane as a ...
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1answer
45 views

Is it possible to make polyethylene in a high school laboratory?

We learned how to make small amounts of ethene from ethanol using sulfuric acid. Is there a way to make a visible amount of polyethylene from that using materials I could get for a school lab? We can'...
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1answer
49 views

Do self-growing hydrogels grow and strengthen infinitely?

Recently, there was a publication [1] (/., YouTube) on self-growing materials using mechanoradically-generated double-network (DN) hydrogels, closely resembling self-strengthening of muscles. We ...
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1answer
51 views

Adhesion of polymerized fats to cast iron

I'm trying to make an informed decision as to which oil is best to use for cast iron seasoning. I've read all kinds of conflicting information online and the only consistency seems to be that ...
2
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1answer
166 views

Polymer Chemistry NMR question [closed]

I am extremely new to both polymer chemistry and NMR. I am struggling with the following question: A proton NMR is used to attempt to quantify the molecular weight of a poly(ethylene oxide) molecule ...
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1answer
46 views

Dissociation behaviour of polyelectrolytes

Assuming a solution of 100 polycationic molecules, each of them carrying 100 amino groups and an apparent pKa of 6.5. Would it mean that, at a pH of 6.5, 50 molecules will be fully protonated 50 ...
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What is ultimate decomposion product of Teflon (PTFE) in environment

There is a lot information available regarding thermal decomposition e.g. burning, but what happens to PTFE in ordinary environmental circumstances? Or if time for degradation is short enough, what ...
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1answer
50 views

How to write correct NMR integrals in a formula?

for my masterthesis I want to include the Equation how I calculate my conversion in a polymer reaction. It is pretty easy, but I still want to write it down. Basicly the equation is: (Integral A ...
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1answer
37 views

What is the refractive index of poly(methacrylamide)?

I've been looking for the index of refraction for poly(methacrylamide). I searched several vendors and in https://polymerdatabase.com/ with no success. Is there any database where I can find this ...
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2answers
210 views

Question during radius of gyration calculation from XYZ trajectoris of atoms

I have molecular dynamic simulation result of 100 polymer molecules (liquid), and I'm trying to calculate the radius of gyration using atomistic mass, molecular mass, and xyz coordinate of atoms. I'm ...
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2answers
72 views

How long does a linear hydrocarbon chain have to be before we call it polyethylene?

Might be a really silly question here but here goes. Polyethylene is a polymer with a repeating unit of just 2 carbon atoms attacked to 2 hydrogens each which connect to other repeat units. This ...
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1answer
127 views

Why is Buna-S called so?

Styrene Butadiene synthetic rubber is also called Buna-S. It is the abbreviation of Butadiene (Bu) Sodium (Na) Styrene (S). Why is Sodium included?
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How to align povidone-iodine molecules in order to look for optical polarization

In this answer I mention how early polarizing filters (e.g. sunglasses) were made by doping a polymer with iodine atoms and then stretching the film to orient the polymer molecules. Electrons donated ...
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1answer
51 views

Role of substituents in radical initialized polymerization

Here, the answer given is (iv), and I don't see the reason why methoxyethene is not forming an addition polymer with radical initiators. Clearly, the first option will form polystyrene and the second, ...
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1answer
96 views

How to remove MEHQ from Methacrylic acid monomer without reduced pressure distillation?

I am aware that the standard way to remove MEHQ from Methacrylic Acid is to perform reduced pressure distillation. The papers I see suggest using ~ 10 Torr pressure to perform distillation. Sandler's ...
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2answers
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Are the bonds in the monomers at the end of a polymer filled or unfilled?

In polymers the bonds between monomers are changed, usually from double to single1, to form a long-chain polymer with the now single bond joining another monomer. But in the monomers at the very ends ...
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What is a “tri-salt polymer” as described by this product that eliminates and prevents mold?

This answer mentions an anti-mold product called Concrobium Mold Control. The FAQ linked on their website says: Q: I see Sodium Carbonate listed on the label. Is Concrobium Mold Control just Sodium ...
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1answer
732 views

Can superglue (cyanoacrylite) be thinned with acetone and still harden?

I'm looking for something with an extremely low viscosity to use as a binder for cold casting iron oxide with very fine detail (it's to make a slotted winding core for an electric motor with $\pu{1mm}$...
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2answers
2k views

Why does lavender oil dissolve plastic?

A few weeks ago I decided to harvest the lavender in my garden and put it through a still to extract the essential oils. The still in question is essentially just an air cooled condenser. I collected ...