Questions tagged [polymers]
For questions about synthetic or natural polymers, their chemical or physical properties, and their synthesis, etc.
624 questions
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Can we revers the process of plastics to fuel
I am a 10th grade student who is trying to convert plastics into fuel.
My question is that when we can make plastic from oil/fuel then can we revers the process?
But we should be able to revers the ...
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Difference between EVA (ethylene vinyl acetate) and VAE (vinyl ethylene acetate)
TL;DR
What the difference between VAE and EVA on molecular level?
I know that EVA is plastic that is waterproof and has a such molecular structure:
But VAE is not waterproof (I've used RDP VAE, mixed ...
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Can SMA (styrene maleic anhydride) resin be used as a dispersant in pigments?
I have checked many materials and they all say that styrene maleic anhydride polymer - SMA resin can be used as a dispersant for pigments. However, I am not very clear about which ester solvent is the ...
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Long-chain polymers for creating large, long-lasting, immortal bubbles
I'm experimenting with different substances to add to a bubble solution to create the largest and longest-lasting bubbles I can make.
Are there any long-chain polymers, whether in their pure form or ...
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The effect of structure on the glass transition temperature of polymers in the case of cis and trans poly 1,4 butadiene
Why does poly trans 1,4 butadiene have a lower glass transition temperature than poly cis 1,4 butadiene?
My reading has led me to understand that a cis double bond lowers the energy barrier of ...
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Is MgCl2 a good polymerization inhibitor?
I've read about the formation of Liesegang pattern and decided to extend this approach to hydrogel mineralization, to see if the same result could be achieved.
Here was my idea: to prepare a PA (poly ...
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Want to follow a polymer paper but can't understand their units
I read a paper that was formulating different polymer mixes where their recipe units were g-1 (see attached image on their recipes). I am assuming that its g%g (grams per 100 grams of material), but I ...
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Oxygen as polymerisation initiator
In my chemistry textbook, when talking about polymerisation, there was a small section about the discovery of polyethylene that was as follows:
The chemists put some ethene in a container at 170C and ...
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Role of ethanol in ethanol - CaCl2 bath used for crosslinking film
In an experiment a dry film of sodium-alginate (polysaccharide) is immersed in a 70% v/v aqueous solution containing 5 % w/v CaCl2. The result is that the Ca2+ crosslinks the polysaccharides.
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What makes polymers have low static/sliding friction?
right now I am looking into polymers in application where they are used for their low friction and high wear resistance such as PTFE, POM or PA6.
I am interested to understand why these polymers have ...
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Hansen solubility parameters and HMPC
Finding solvents for HMPC
I am trying to gather information about hydroxypropyl methylcellulose (HPMC) — a.k.a. hypromellose or under the trade name Methocel — solubility in a variety of solvents. ...
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What kind of polymeric anions can be made of boron and sulfur?
Boron sulfide is polymeric. What happens to that structure if another sulfide (or multiple sulfides) is added? Is it always going to make a compound with small thioborate (not sure if this is the ...
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Why poly(isobutylene) is a rubber while poly(propylene) is a plastic
I was asked by my professor why poly(isobutylene) was a rubber while poly(propylene) was a plastic.
The reason probably involves the fact that PIB is more entangled than PP.
My attempt:
i) The trans ...
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Ring opening polymerization of polylactic acid using tin(II) 2-ethylhexanoate
I am writing my thesis on polymerization of pla. i used following method: https://www.chimia.ch/chimia/article/view/2012_951/4616
I am writing theory about the ROP of polylactic acid using the ...
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How does Benzyl alcohol prevent BADGE (BPA + Epichlorohydrin) + IPD + Hexane-1,6-diamine from reacting?
I believe I understand how epoxy reactions work in general: The NH2 groups in the Hexane-1,6-diamine will react with the C2O triangles in the Bisphenol A diglycidyl ether to form longer polymer chains....
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Oligomerisation of L-Lactic acid to Prepolymer
I am working on my Thesis in which i synthesised PLA out of L-lactic acid. I am using the Methods from a research paper from the HEIA-FR which i linked here aswell.
Method and Paper that I used
The ...
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How to convert a polymer having OH groups to azide groups?
I am using Polypropylene glycol (PPG). I want to convert the OH groups in PPG to N3 (azide group). I tried to follow a reference which can be summarized as the alcohol was treated with PPh3, Iodine, ...
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What is the difference between these two polymers?
I am looking at purchasing a chemical that will release a small amount of HF gas and have been referred to a polymer called PVPHF. After looking it up, though, it appears that there are two compounds ...
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Could this glassy "Amber-Like" polymer used to store DNA be exposed to sunlight?
An interesting article, that I came across today, talked about the ongoing research into storing DNA at room temperature essentially with glassy "amber-like" polymers. Before talking about ...
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What role does CaCl2 play in a gelation medium?
To produce sodium alginate beads coated with chitosan, following procedure was undertaken:
Sodium alginate was dissolved in distilled water at a concentration of 4% (...) The gelation medium was ...
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drying polymers / FDM 3D printer filaments
My understanding is PLA can absorb 1%, and some others (ABS?) can absorb up to 10% moisture. In order to dry a polymer, is additional (more than room temperature) heat needed (like a filament dryer/...
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Biodegradability of Polymers
Nylon-6 is a polymer of 5-amino caproic acid (although it is generally prepared by hydrolysis of caprolactam) and Nylon-2-Nylon-6 is a copolymer of glycine and 5-amino caproic acid.
While Nylon-2-...
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Synthesis of polypropylene
So, I have two questions regarding the synthesis of polypropylene:
I have tried looking everywhere but couldn't find a detailed mechanism for the termination step of the synthesis of polypropylene (...
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What is 'spray foam' or 'expanding foam'?
At the wikipedia are:
Spray foam (expanding foam in the UK) is a chemical product created by two materials, isocyanate and polyol resin, which react when mixed with each other and expand up to 30-60 ...
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Difference between polyethylene sulfonate and Nafion?
Nafion is a cation-exchange membrane that I would like to build a chlor-alkali cell, but unfortunately it's crazy expensive(and comes in ridiculously large sizes). Its functional group, the sulfonate ...
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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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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 ...
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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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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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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 ...
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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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