Theory

Here, we will post theories and helpful, need-to-know information associated with the development of the shooters and formula.

Webbing - Polymers: A Review
Courtesy of White_widow

Webbing falls under the category of a mixture of Chemistry and physics. The official name for the field is material science. Let's get into the very basics. This is true of all polymers.

Everything in the universe is made of energy. That energy is expressed in the form of atoms. Atoms are therefore the legos of reality. This is nothing new, and nothing that you didn't already know. Differing atoms come together to create molecules, or if they join up to themselves, elements. Molecules are small chains of atoms.

Now certain linear molecules are called monomers. Monomers are links in the chain. Polymers are the full chain of monomers. Now it is important to notice that monomers sizes will drastically effect properties. For example if you look at nylons, the structure is made longer, but not different. Just the length will change, and it will change the properties. The same is true in cyanoacrylates. The properties are the different but the chains are just different lengths. Only one of the different cyanoacrylate formulas will be biodegradable and safe for skin. Just the addition of an atom can turn some materials acidic. It's important to check out different materials to see how different properties manifest themselves.

As said before, there are more ways than one to create similar properties. For example flame retardant material can be that way because it has a super high melting point, because it has high insulation properties, or because it carbonizes or caramelizes at certain temperatures.

Now, the experiments that bring molecules together to make these polymer chains are called polymerization. This is where chains of monomers will bond to each other through cross-links, or specific bonds. There are many types of polymerization. The one that we want to focus on is called contact polymerization. There are others, but this one is the least complex, and the easiest to take advantage of. It's a single touch and it creates a reaction. If you know anything about chemistry, that is how you'll use that knowledge of reactions. Luckily for us when monomer chains cross-link, it's generally a single replacement. Of course it takes time to predict where it will happen, but nylon wasn't created by accident. Neither will the webbing formula.

When it comes to monomers in the chain, it's possible to add monomers of differing types together. In fact that's probably what we're going to have to do to gain such high tensile strength and elastomeric power without vulcanization. Vulcanization is the cross-linking of  sulfur into a rubber with heat or a catalyst. It makes it much tougher.

Webbing - The Theory of Adhesive Cohesion
Courtesy of White_widow

In basic polymer science, we learn that properties are gained by cross-links. However, with the advent of hydrogen bonding, it became apparent that cross-links can be made temporary so that the material would still have a life cycle instead of becoming an environmentally destroying thermoset. The theory of Adhesive cohesion states that a polymer, instead of being chemically cross-linked, can still gain high tensile strength by using a glue on the molecular level. An example of this is found in oyster-style nano-plastics. Layers help make it strong. If we can't create layers though, we can at least make sure that layers are bonded by a strong glue. 


In layman's terms, all materials in the webbing gain a temporary chemical bond due to the adhesive working with hydrogen bonding. The glue is literally acting cohesive. It's not supposed to, but theoretically can if the glue is made of two parts: a resin and rubber.


Adhesion is the bonding of two different materials, while cohesion bonds similar materials. because the glue is two part, the rubber will be bonded to the plastic by the tackifier. This can allow us to bypass synthesizing two reactants. (that would take too long and would be dangerous) This theory allows us to make a one part formula that is activated by compression in the spinneret. When the molecules are pushed together, that's when they form the bond. That is what will make sure that they stay in strands. It is important though for them to be in a gel form, because it is important that the end splatters.

Webbing - Properties and Description
Courtesy of White_widow

Back in the day, there was a book. It was the Spider-man manual. It had a more in depth analysis on properties, but for our purpose we just want a few basics.

THE BIG THREE

When it comes to webbing, it doesn't really matter if we have every single property. What matters is that for the most part, we only need three of them. Once you get these three, you are free to stop working on the webbing, unless you need it for something specific.

Tensile strength- In the old PS1 game, Spider-man, there was a loading screen that talked about spidey's webbing being stronger than steel of the same diameter. While we don't have to go that far, we can use that knowledge to find out how that happens. Very specific polymers have the property, so it's easy to figure out which elements one needs to make it work. We are shooting for at least 50 MPa, or Megapascals. It's a scientific unit of pressure. Steel is anywhere from 1,000 MPa up. Kevlar is about 3,600 MPa.

Adhesion- Spidey's super-strong rope would be nothing if it didn't bond to anything. It seems that Spidey's web has an adhesive strength that is as strong as his webbing. There are only a few glues that match the strength of webbing, and only two groups that match the speed of bond without some solvent cheats.

Convenient state change- Spidey's webbing is technically a fluid. Well it is at least as it passes through the spinneret. While the official record says that this is caused by shear thinning (which it totally might), that's hard to believe, because adhesives that are elastomeric in nature tend to undergo strain crystallization. Strain crystallization is like the thinner cousin of the huskier shear thickening property. All we need to know is that it has to be a fluid in the shooter, and a solid outside of the shooter. 

Other Properties.

Elastomeric structure -This one is pretty easy to figure out. These polymers tend to be amorphous in nature. They crystallize when they are stretched. That's why when you pull a rubber band, it's easier at first, but it begins to fight you. Some rubber, like the kind in tires have been vulcanized, but we can't include that property because it makes it too hard to dissolve. Examples are neoprene and latex. Webbing is an example of latex, a suspension of an elastomeric compound.

Degradation- This is the one property that no other material has. No material degrades in an hour. There are materials that will be dissolved by solvent that quickly, destroyed by sunlight over the period of days, or naturally taken up into the earth via bacteria, but there is no hour long material.

Flame retardant- This one is pretty easy to replicate because it comes in so many forms. We could add one material (borax) and give it flame retardency. There are other methods: heat-linked glues, nomex properties, caramelizing, high melting point, high insulation properties, and lack oxygen all play a factor. It's really quite simple though. In the fire triangle, we are taking away the fuel.

Translucent- Not super important, but if you will use a UV based adhesive, it will be your whole world. Basically, this property allows light to be passed through it. Magnesium oxide has this property.

Conduction- Spidey's web conducts electricity. That's why whenever he covers shockers hands, he freaks out. He is being short circuited. Others may say that it is only semi-conductive.

Non-toxic nature- Spider-man's webbing is not dangerous to the human body. In fact, so much so that it's like the equivalent of having gum in your hair. It acts as a great medical adhesive, meaning that it either resists water or absorbs it and expands. Even when it degrades after an hour, it can just blow away.

Expansion rate- Come on. Do you expect us to believe that such small cartridges could generate so much webbing? Not really. Even Stan Lee had mentioned in an interview how he had not intended for Spider-man to use so much of it. In the early comics he certainly never swung on it for too long. One line or two, never more. However, this can be conceded to because of the old theme song. "Can he swing from a THREAD? Take a look overhead." These days, he's holding onto a rope. It only makes sense that if he is using more webbing, he is forcing it to expand. This can allow him to use the amount that is in the cartridge. However, even still the expansion rate it still rather ridiculous. It's an expansive factor akin to 6000-8000x (depending on height) Aerogels, the most airy materials that hold shape are 99% air. Even the most powerful foam is about 2000x the expansion. There would need to be bigger cartridges.

Now this does not include the shape of the web, we'll get to that after we work on the properties. There are some properties that only the shooter can generate. For example, the comics say that the webbing is shaped like that due to electro-stactic forces. Nope. That was all the shooter. The shooter is also responsible for drawing the polymer, it contributes to expansion rate, and it determines the thickness of the web.

Shooter - Knot Theory
Courtesy of White_widow and Cracked.com

"You stuff your headphones into your pocket, take them out half an hour later and curse as you try to untie a knot that looks like it was impossible to have formed on its own, like you have tiny knot-tying elves in your pockets trying to screw with you.

It's the same with your computer cables, and the Christmas lights in your attic, and your garden hose. In fact, everything in your home that is capable of twisting into a knot seems to be involved in a giant conspiracy against your sanity. And it always pisses you off, because there's no reason for it -- why would a bunch of wire that was in a nice loop when you stored it suddenly be a tangled mess later?

The Science:

Don't think that science has just been asleep at the wheel on this one; there is an entire mathematical discipline that specializes in how seemingly random tangles form. Knot theory is in fact one of the more popular pastimes among the mathematically well-endowed, and it focuses entirely on the "How the hell do things get tangled?" dilemma.

And here's what they have found out: It is a near-mathematical certainty that a wire/string/hose/etc. of any length will knot in storage. To put it simply (and it gets infinitely complicated), there is only one way for a cable to be straight, but a massive number of ways it can get tangled. Scientists have found literally hundreds of separate, unique types of individual knot, or "prime knots," and they can be combined in infinite ways. You could go your whole life and never see the same knot twice.

So any time you have a bunch of long, flexible objects (or, in the garden hose scenario, one really long object in multiple loops), the objects link in a number of places. When there's enough contact points, and the objects are long and slim enough, the chances for these objects not getting into one of those trillions of knot states is downright astronomical. The more contact points, the more possible knotted states.

At some point, it's just easier to use a bowie knife and buy a load of cords.

So even a little motion -- jostling the box of Christmas lights when you move it, a change in temperature causing your garden hose to shrink a tiny bit -- makes those states catastrophically accumulate, often within seconds. Put the headphones in your backpack, walk across campus, boom: You have descended into knot hell.

Can It Be Fixed?

Yes and no.

The actual knotting will happen no matter what. Sure, the crucial element is motion, so restricting that by neatly arranging the cables and securing them with, say, cable clips will do the trick. But if you are the kind of person who considers that an option, chances are your cables are neatly arranged and alphabetized already.

If the movement can't be restricted, like with those headphone cables, you can either muster up the patience and technique to roll them up neatly or, failing that, just bury them at the bottom of the bag under something heavy and hope for the best."


In other words, any group of wires, cables, or fibers will partner up if left to move quickly in a tight space. If we can make the fibers solidify the second they leave the metal spinneret, and put a little more narrow cone shape restricting the movements, it WILL create a rope. The statistical odds for it are immense. This is increased due to the PSA or pressure sensitive adhesive.

Webbing - Liquid Duct Tape
Courtesy of White_widow

Webbing is strong, it's flexible, and a little goes a long way in sticking power. 100 strands of duct tape can suspend a car, four strands can hold an obese man sitting on it. The strength comes from cotton backing, or woven cellulose strands. The polyethylene only provides sealing power. Look at your average roll of duct tape. It doesn't take a lot of cotton to produce that strength does it? It looks like a plaid net. So what does that mean? The adhesive itself is strong enough to hold a man to a wall. I bet that you could swing with three strands of duct tape, maybe four. this is what we need to model our webbing on. Forget silly string, we want duct tape.

So in our quest for liquid duct tape, we need to remember a few things. The strength comes solely from the cotton. Odd though isn't it? It can hold about 80 lbs with one strand vertically (60 lbs horizontally), but they designed it to be easily torn. Each strand is easily broken, but collectively, they are strong. We want ours to not tear. To do this, we make sure all of the strands are close together. We don't want a lot space between the strands. A little is good, but not a great deal. We will be using cellulose acetate, or methyl cellulose.

The second thing to remember is that the rubber adhesive is as strong as the cotton, but only in adhesive strength. The heat is going to be a challenge but the heat will travel directly into the acetone, so design is everything. The webbing should probably be designed to splatter a bit. That way, the adhesive will maximized contact with a surface of choice.

Finally, it should be noted that for this to work, each part must be able to do its thing. So the liquids must be immiscible, Also, the formula has to contain much more cellulose than glue.

To do everything that Peter's webbing can, we need to model it on the real world equivalent. Liquid duct tape... that's what we're making.

Practicalities - Why Swinging Is Not Likely
Courtesy of Nolder

Some of you have been wondering about swinging. The problem is that the web has to support the swinger's weight and the centripital force which will be greatest at the bottom of his swing.

1.) Consider that Peter Parker is 100 kg (around 220 lbs). That's pretty heavy but it gives us some some safety room and it makes the calculation a whole lot easier.

2.) Many sources state the Spider-Man can go 80 mph. This seems pretty high considering a lot of roller coasters max out at arround that speed. It's a slow day; Spidey doesn't have anywhere to be for once. So he's just cruisin'. Let's say he's going 45 mph, or about 20 m/s

3.) Let's say his web is 9 or 10 storys long (9 or 10 floors) so its about 30 meters

We use this formula to calculate how much the web would actually have to hold

F = M(V^2)/R

M is the mass, which is 100 kg

V is the velocity, 20m/s

R is the radius (his swings are really a series of half circles) which is 30 meters

F = M(V^2)/R = 100 kg * (20 m/s) ^2 / 30 m = 10^3 N

1000 N or 1000 newtons is 224 pounds. But don't get all excited yet. We still have to add a gravitational force of:

Fg = MG = 10^3 N.

So it's really like his web has to hold 2 x 10^3 N, or 450 pounds. More than twice his weight.

Granted, this is for a 220 pound Peter Parker, but it doesn't take into account other variables AND this is him going at a relatively slow speed.

If,

A) He weighed more

B) He was swinging faster or

C) His web was shorter

The web would have to hold greater force.

Let me make it clear that if you weigh half that he does (110 lbs), that does NOT mean the web will only have to hold half of what we calculated. Velocity, radius, and gravitational force would remain the same reguardless of your weight unless you changed them too.

Considering that we are looking at holding around 80lbs (according to White_widow), it doesn't look like we'll be swinging anytime soon.

Read more spiderman physics here:

http://www.qwantz.com/fanart/spiderman.pdf