A large molecule (macromolecule) composed of repeating structural units.

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What is the exothermic reaction of superglue with cardboard?

I glued a sheet of paper to a cardboard package using superglue. To my surprise the paper became very warm. What kind of reaction is it? (The glue in question is labelled with Ethyl ...
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41 views

Residual stress in polymer coatings

A paper talks about the residual stress when coating polymers. It says that residual stress is the sum of the "heat stress" (due to the difference in thermal expansion coefficients) and the "shrinkage ...
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37 views

Why no thermal expansion for camping tents?

I know that solid materials expand when heated, which is called thermal expansion. But what is happening to tent square or tent canvas of (plastic?) camping tents? I have noticed, that during the ...
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28 views

Ethyl alcohols use on polycarbonate and acrylics

I have an interesting question about the use of ethyl alcohol on polycarbonate windshields. I have had friends asking me about the use of Pledge Multi-Surface cleaner on their windshields. Some ...
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33 views

What is an effective fabric-friendly solvent for aluminium chlorohydrate?

I have recently found out that the white/yellowish "sweat" stains one occasionally finds on t-shirts might be aluminium chlorohydrate polymers. While talk about aluminium and antiperspirants is all ...
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539 views

What makes teflon such a strong material?

I don't know much about polymers but recently teflon made me get addicted to study their properties and nature. As far as I know, the teflon polymer contains fluorine which is one of the most ...
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14 views

Polymer Crystallinity

See the following question: I think the answer is A because of the hydrogen bond in the side group, thus the degree of secondary bonding between parallel chain segments is higher. Is my thinking ...
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35 views

Monomers and polymers

At Wikipedia a monomer is defined to be a molecule that may bind chemically to other molecules to form a polymer. A polymer is defined to be a molecule composed of many monomers. These ...
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24 views

What is the chemical composition of VOC's off-gassed from polyurethane?

I understand that all polyurethane (PU) materials off gas VOCs. I tried finding the % composition of the gases off-gassed by PU, but I am not able to get satisfactory answer. On the same note, why are ...
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38 views

Modelling planar ring molecules and their evolutions

This is the next step of my previous question. I am trying to simulate a circular chain (ring) of molecules which are planar (two dimensional). What I do is take a planar unknot and embed it into a ...
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31 views

Modelling planar molecules and their evolutions

I am trying to simulate a chain of molecules which are planar. Can anyone please give me an example of the molecular chain which can stay as planar with it's minimum energy state is planar. A ...
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29 views

How do I lookup a polymer by its structure?

This is more of a meta-chemistry question, but, here goes... Given the structure of a polymer, how can I search online for which polymer it is? Specifically, I have an image like this: I'd also ...
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67 views

What are the physico-chemical processes at play in ironing of clothes?

The process of ironing of clothes removes (to a large extend) the wrinkles that where introduced in the clothes while drying. Obviously this has to be some physico-chemical process that is ...
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104 views

Safety concerns - Heating PMMA (acrylic glass) and fluorinated polymers

I have some plastic optical fiber, which consists of a thin core of PMMA (polymethyl methacrylate), covered by a fluorinated polymer. I would like to heat a bundle of these fibers to ~130 degrees, in ...
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63 views

Alginate nanoparticles

I want to produce alginate nanoparticles from NaAlg. I choosed nebulizing NaAlg solution into $\ce{CaCl2}$ solution but 2% (m/v) NaAlg solution is quite viscous. What should I do to make it inviscid? ...
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73 views

How much UV lamp power is needed to initiate radical polymerization?

I'm looking to purchase a UV lamp for initating some radical polymerizations. Is a hand lamp like the type for examining TLC plates (5-10W, like this) enough power to do this, or do I have to buy ...
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59 views

Does supersaturated caffeine polymerize?

I tried preparing a supersaturated solution of caffeine by mixing anhydrous caffeine powder with water in a thin Turkish tea glass and heating it up over a candle (desperate times...). This worked ...
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36 views

Polymers with no molecular mass distribution?

What sort of ideal conditions are required - theoretically - to conduct polymerization reactions to make all the macromolecules end up with exactly the same molecular mass, just like the products in ...
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53 views

How to synthesize t-Boc protected derivative of PVA

I've been toying with different potential recipes for DIY photoresist. My current favored design is a chemically amplified resist based on PVA (poly(vinyl alcohol)). For those who are unaware, a CAR ...
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2answers
121 views

What type of sensor technologies exist to determine the chemical composition of a polymer?

Let's say I have several pieces of trash and each is made with a different type of material like: Plastic bottle : High Density Polyethylene (HDPE) Cereal box : Paperboard & Epichlorohydrin ...
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165 views

How to liquefy or extract water from superabsorbent polymer

I am finding a good way to liquefy or extract water from superabsorbent polymer. From what I remember it was salt that can liquefy it. Since salt when dissolve will have sodium cation and there for ...
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43 views

What chemical properties make some grassses usable for producing textile fabrics?

Textile Fabrics are made out of cellulose fibres that can be derived from cotton or bamboo. As far as I know all grasses contain cellulose, so why are only a few grasses used? What makes them so ...
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148 views

A chemistry approach to environmentally friendly yoga mats… NBR, NR, TPE, PER [closed]

I'm currently seeking your expertise while creating a line of environmentally friendly yoga mats, and I apologize in advance if any chemistry knowledge of mine has been absent since college and I lack ...
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106 views

Molding/shaping sodium polyacrylate?

I've been researching sodium polyacrylate, which normally comes as those "aqua gems" for plants, or fake snow. Specifically, I've been hoping to find information on molding, casting, or otherwise ...
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What are Thermoplastic Elastomers (TPE) and what is their environmental impact [closed]

TPE is often touted as a more environmental alternative to PVC (at least for yoga mats). What are TPEs and what raw materials are they manufactured from. What uses and properties do they have? Are ...
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56 views

Electrical and Mechanical properties of Sodium Polyacrylate?

I was looking for a chart with electrical and mechanical properties of the Super Absorbent Polymer Sodium Polyacrylate(WaterLock) and could not find one. Please help.
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103 views

Biopolymers as alternative for PVC and PU?

I'm working on a project making a product line more sustainable, environmentally friendly and ready for recycling. Now I'm searching for good and suitable biopolymers for a part of the product that ...
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118 views

Equations for UV degradation of condensation polymers

I'm an A-level student studying the F324 unit of OCR GCE Chemistry 'A'. The exact question is Explain how condensation polymers may be photodegradable. Equations needed! I understand: What a ...
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453 views

What is Polymer Environmental Resin (PER)?

I'm no chemist and I probably wouldn't understand any technical answer but... I'm investigating the environmental impacts of various materials as compared to PVC and this is one that crops up ...
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74 views

Can freezing break up sugar polymers?

I recently freezed a huge bunch of apple slices, and thawed them again a few days later. After thawing, I noticed a few things compared to a batch that I had put in the fridge (no freezing) The ...
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27 views

Is there a correlation between the susceptibility of a polymer to undergo hydrolysis and it's melting point?

As per topic, I was wondering why the Tm of the polymers PGA, PLA and PLGA are in the following order. Does it correlate to their ability to undergo hydrolysis? PGA>PLA>PLGA
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59 views

Food safe basic polyelectrolytes?

Pectin is an example of a food safe polyelectrolyte. It acts as an acid because it is a proton donor and develops negative charges along the polymer. Can you think of any examples of food safe ...
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65 views

Flory Huggins Theory

For an ideal chain, Flory Huggins theory gives us a distribution which is like a Gaussian. $$P(l, r) \sim \left(\frac{3}{2 \pi l^2}\right)^{3/2} e^{\frac{-3 r^2}{2 l^2}}$$ where, $l$ is the monomer ...
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112 views

Does variations in air pressure affect the melting point of PLA and ABS while 3D Printing?

Tight temperature controls are needed to ensure that the filament used in fabrication does not begin to "ooze". In places where the air pressure rises and drops during the course of the day there may ...
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Can a polymer have different resonance structures?

Several organic compounds have resonance structures, but can a polymer have resonance structures?
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45 views

Plastic: Reputable Publications

I would just like some reputable textbooks and or publication companies that have extensive research on plastics, as, for example, dealing with life cycles of plastics, degradation factors, effect on ...
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166 views

Solid hydrophilic transparant materials that don't dissolve in water

I am looking for hydrophilic transparant materials which are solid at room temperature and that don't dissolve in water. I need these for an experiment in which I condense droplets on a plate made out ...
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1answer
136 views

How long can polyethylene molecules be?

In this video, Steve Spangler says the substance he is using (a polyethylene oxide): http://www.youtube.com/watch?v=m-88M75_PCI He mentions that one molecule would go to the moon and back twice! I ...
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924 views

Easily removable material that sticks to skin

I am looking for some kind of material that can be used to easily latch something to someone's finger. This is for a first year engineering project. The idea is to use this material to latch small ...
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1answer
708 views

How would I select the strongest Plastic Material?

Plastic Selection I'm going to have an online machine shop build a part for me using a CAD drawing that I specify. Typically, these parts are made of Aluminum, but this manufacturer also mills parts ...
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30 views

Why do big thermoplastics (like Polytetrafluoroethylene) behave like thermosets?

Why do big thermoplastics (like Polytetrafluoroethylene) behave like thermosets? I know for sure it has to do with the van der Waals force and the fact that the molecules are huge, but why? Why does a ...
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50 views

What is a 'Trace Crossing'?

I'm reading about electrodeposition of conductive polymers in a chemistry textbook, and the author mentions 'trace-crossing' in the 'potentiodynamic response'. From the context I can figure out that ...
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2k views

A thermoset or a thermoplastic?

How do you know if a polymer is a thermoset or a thermoplastic? For example: hydroxybutanoic acid 2-amino-3- hydroxybutanoic acid (I am not sure if these are correct in English) I know what ...
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Why are smoke odors persistent in fabrics?

Obviously smoke is very complex, but apparently phenol compounds are the main components of wood smoke that produce the characteristic odor. (One of more significant of these compounds seems to be ...
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258 views

Polymer Slurry Fact

I watched a video on the construction of Burj Khalifa, Dubai. The construction engineers answered that they're using a special type of protection known as Cathodic protection to protect from the ...
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4k views

How to find the band gap for a compound?

I have processed a si/polymer hybrid using a silane coupling agent which I need to determine the energy gap / band gap. Would you please let me know the procedure to go about determining the band ...
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Are there any general chemical rules for choosing initiators for a polymerization reaction?

I'm working with some very basic free-radical initiated polymerization reactions. For the most part, I just follow a recipe I'm given (by a member of my group or the broader literature), it works, and ...
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3k views

The Chemistry behind creating Polylactic Acid (PLA)

I've seen a few videos of persons creating plastics from starch by adding an acid, glycerol, and water, however no explanation of the chemistry. Does anyone know what $\ce{(C6H10O5)_{n} + C3H8O3 + ...
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Stiffness of chewing gum

My Sister asked me this: "Why is it that when we chew gum, it is soft and mushy to begin with , but slowly gets firmer and firmer like after 20 mins of chewing?" I think it is because when we ...
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How is silica bead bonded into polystyrene?

What kind of bonds silica bead forms with polystyrene? Silica is now as ~100 $\mu$m spherical particles in bulk polystyrene that is made by melting. How can I bond the silica particles more ...