Foam » polyethylene foam http://www.nrfoam.org Fri, 16 Apr 2010 20:59:02 +0000 en hourly 1 http://wordpress.org/?v=3.2.1 How do the properties of plastic differ and for which processes or applications are they best suited? http://www.nrfoam.org/polyethylene-foam/how-do-the-properties-of-plastic-differ-and-for-which-processes-or-applications-are-they-best-suited/ http://www.nrfoam.org/polyethylene-foam/how-do-the-properties-of-plastic-differ-and-for-which-processes-or-applications-are-they-best-suited/#comments Wed, 17 Mar 2010 04:28:00 +0000 admin http://www.nrfoam.org/polyethylene-foam/how-do-the-properties-of-plastic-differ-and-for-which-processes-or-applications-are-they-best-suited Continue reading →]]> Materials: Polyethylene Terephthalate (PET)
High-Density Polyethylene (HDPE)
Polystyrene Foam (PS)

Polyethylene Terephthalate (PET) – Is a very clean and strong plastic . It is used almost exclusively for plastic beverage bottles because it doesn’t impart a plastic taste to the product, plus the plastic is dense enough and strong enought o resist high pressure carbonation without it leaking thru plastic molecules. It is also easy to recycle and is made into carpet fiber (polyester) and clothes because of the high quality of the plastic

High-Density Polyethylene (HDPE) – has higher strength than regular plastic, so is good for milk jugs, garbage bags , Plastic chairs and plastic water pipes etc.

Polystyrene Foam (PS) – This is the common stryofoam everyone knows. Here a polystyrene plastic , which is cheap and fairly rigid, is treated with a blowing agent that forms air bubbles into the melted polystryrene. The air bubbles incorporated in the plastic make it ideal for lightweight shipping packaging and it is very moldable around specialty items.
It also is used heavily in the insulation business to make insulation panels and doors for superior insulation in homes and commercial businesses. It is waterproof and bugs don’t eat it and it doesn’t rot.

]]> http://www.nrfoam.org/polyethylene-foam/how-do-the-properties-of-plastic-differ-and-for-which-processes-or-applications-are-they-best-suited/feed/ 1 help! im new to solidworks!? http://www.nrfoam.org/polyethylene-foam/help-im-new-to-solidworks/ http://www.nrfoam.org/polyethylene-foam/help-im-new-to-solidworks/#comments Mon, 15 Feb 2010 01:28:05 +0000 admin http://www.nrfoam.org/polyethylene-foam/help-im-new-to-solidworks Continue reading →]]> i need help setting the material.
i am drawing bumpers for a robot for my school’s robotics team. i went under materials, but it doesn’t have closed cell polyethylene foam, which is what pool noodles are made of. how do i set the material to that?

Consider asking your question in the SolidWorks forum. There are thousands of experienced SolidWorks users there who can help.

https://forum.solidworks.com

Matt / SolidWorks

]]> http://www.nrfoam.org/polyethylene-foam/help-im-new-to-solidworks/feed/ 1 Help with science: chemistry? http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry-2/ http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry-2/#comments Wed, 13 Jan 2010 15:15:08 +0000 admin http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry-2 Continue reading →]]> I have a lot of homework questions i don’t get some of them. Please help me with them:

1. Low-density polyethylene is a plastic that can be stretched somewhat without breaking it. Why is this property useful for disposable shopping bags?

2. What are two physical changes that cooling a hot substance may result in? (I wrote liquids and solids, but I have no idea if it is right or wrong)

3. Why will water form droplets on a smooth surface, such as a counter top?

4. Metal foams are 75 to 95 percent air. What effect does this have on the density of metal foam compared to solid metal?

5. If water freezes inside of a building’s water pipes, the pipes may burst. Explain why this happens.

6. Consider a homogeneous mixture, such as a salt solution, anda heterogeneous mixture, such as rice and pebbles. Suggest and compare how you could separate the substances within each type of mixture.

YOU DO NOT HAVE TO ANSWER ALL QUESTIONS!!!!!!!!!!

Thank you soooooo much!!! :D

1. elastic property – important to allow plastic bags to withstand heavier products and stretch to fit products.

2. Change in volume, change in state (solid – liquid, liquid – gas), change in temperature (no points for that answer lol). Think of a physical change as something that can be easily reversed. For example, you freeze water it becomes ice, you can then melt the ice to become water (it has changed its state). On the other hand a chemical change is a change in the actual product that can not be reversed. For example, baking a cake, you start of with a whole lot of ingredients then once they are mixed and baked to make a cake you can not reverse the process to get all the ingredients again. (Hope this makes these types of questions a little easier to understand).

3. This is a result of intermolecular forces – attractions between molecules. Water has a strong intermolecular for therefore drops will form on a smooth surface to increase the surface area of the water. (not really the best answer to this question I am sorry but you must have learnt this go back over notes and look for keywords such as intermolecular forces, cohesive forces etc).

4. This reduces the density as it will be light than solid metal due to the high amount of air in the foam. density is the weight of an object compared to its volume/ size. For example if you have a shot-putt that weighs 4kg and a tennis ball, although they are a similar size the tennis ball is no where near as heavy. This is because the shot-putt is more dense.

5. Similar to the answer in Q2. A change in state changes the volume – freezing water increases the volume, this is because molecules have low energy and are not moving freely therefore a solid is formed.

6. For the homogeneous mixture you could just evaporate the water so that you are left with the salt. For the heterogeneous mixture you could use sieving to separate the particles.

Hope this helps out, do just double check what I have written though becuase it has been a while since I done this chemistry lol (I’m assuming you are in secondary school?)

]]> http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry-2/feed/ 1 Help with science: chemistry? http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry/ http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry/#comments Mon, 04 Jan 2010 09:43:03 +0000 admin http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry Continue reading →]]> I have a lot of homework questions i don’t get some of them. Please help me with them:

1. Low-density polyethylene is a plastic that can be stretched somewhat without breaking it. Why is this property useful for disposable shopping bags?

2. What are two physical changes that cooling a hot substance may result in? (I wrote liquids and solids, but I have no idea if it is right or wrong)

3. Why will water form droplets on a smooth surface, such as a counter top?

4. Metal foams are 75 to 95 percent air. What effect does this have on the density of metal foam compared to solid metal?

5. If water freezes inside of a building’s water pipes, the pipes may burst. Explain why this happens.

6. Consider a homogeneous mixture, such as a salt solution, anda heterogeneous mixture, such as rice and pebbles. Suggest and compare how you could separate the substances within each type of mixture.

YOU DO NOT HAVE TO ANSWER ALL QUESTIONS!!!!!!!!!!

Thank you soooooo much!!! :D

1. elastic property – important to allow plastic bags to withstand heavier products and stretch to fit products.

2. Change in volume, change in state (solid – liquid, liquid – gas), change in temperature (no points for that answer lol). Think of a physical change as something that can be easily reversed. For example, you freeze water it becomes ice, you can then melt the ice to become water (it has changed its state). On the other hand a chemical change is a change in the actual product that can not be reversed. For example, baking a cake, you start of with a whole lot of ingredients then once they are mixed and baked to make a cake you can not reverse the process to get all the ingredients again. (Hope this makes these types of questions a little easier to understand).

3. This is a result of intermolecular forces – attractions between molecules. Water has a strong intermolecular for therefore drops will form on a smooth surface to increase the surface area of the water. (not really the best answer to this question I am sorry but you must have learnt this go back over notes and look for keywords such as intermolecular forces, cohesive forces etc).

4. This reduces the density as it will be light than solid metal due to the high amount of air in the foam. density is the weight of an object compared to its volume/ size. For example if you have a shot-putt that weighs 4kg and a tennis ball, although they are a similar size the tennis ball is no where near as heavy. This is because the shot-putt is more dense.

5. Similar to the answer in Q2. A change in state changes the volume – freezing water increases the volume, this is because molecules have low energy and are not moving freely therefore a solid is formed.

6. For the homogeneous mixture you could just evaporate the water so that you are left with the salt. For the heterogeneous mixture you could use sieving to separate the particles.

Hope this helps out, do just double check what I have written though becuase it has been a while since I done this chemistry lol (I’m assuming you are in secondary school?)

]]> http://www.nrfoam.org/polyethylene-foam/help-with-science-chemistry/feed/ 0 Where can you buy foam that can be cut to custom fit to put mechanical or specific parts in a case or drawer? http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-3/ http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-3/#comments Thu, 31 Dec 2009 19:13:02 +0000 admin http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-3 Continue reading →]]> I have to buy it in a store not online.
I want maybe polyethylene or polyurethane.
Here’s what I have in mind if my description wasn’t coherent:

http://www.amcases.com/images/FoamInsert…

http://www.onboard.tv/images/product_ima…

http://shashinki.com/shop/images/PLC-160…

I can’t see your links but you might want to look in your telephone yellow pages for "foam suppliers"… there should be at least one in most cities. They sell all kinds of foam and generally will also cut it for an extra fee.

You might also want to check out or ask at photography stores (*real* ones) since a lot of photographers carry their lenses and various other pieces in carriers, nestled into shaped-foam sheets.

HTH,

Diane B.

]]> http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-3/feed/ 2 Where can you buy foam that can be cut to custom fit to put mechanical or specific parts in a case or drawer? http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-2/ http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-2/#comments Wed, 30 Sep 2009 03:18:09 +0000 admin http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-2 I have to buy it in a store not online.
I want maybe polyethylene or polyurethane.
Here’s what I have in mind if my description wasn’t coherent:

http://www.amcases.com/images/FoamInsert…

http://www.onboard.tv/images/product_ima…

http://shashinki.com/shop/images/PLC-160…

All your links are broken.

]]> http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer-2/feed/ 2 Where can I buy closed cell foam? http://www.nrfoam.org/polyethylene-foam/where-can-i-buy-closed-cell-foam/ http://www.nrfoam.org/polyethylene-foam/where-can-i-buy-closed-cell-foam/#comments Sat, 26 Sep 2009 03:08:02 +0000 admin http://www.nrfoam.org/polyethylene-foam/where-can-i-buy-closed-cell-foam Continue reading →]]> Does anyone know where I can buy some polyethylene closed cell form, specifically major or local stores? I am trying to put some of this foam on my floor to muffle footsteps and noise for the people living right under us. I want to go to a store where they sell it so that I can feel samples so that I know what I am buying.

I highly recommend buy it from…

http://www.amazon.com/gp/redirect.html?ie=UTF8&location=http%3A%2F%2Fwww.amazon.com%2Fs%3Fie%3DUTF8%26x%3D13%26ref%255F%3Dnb%255Fss%26y%3D15%26field-keywords%3DPolyethylene%2520closed-cell%26url%3Dsearch-alias%253Daps&tag=aor-sale-20&linkCode=ur2&camp=1789&creative=390957

The best prices and maybe free shipping sometime from the page I bookmark.
Hope you find your favorite. Good Luck!

]]> http://www.nrfoam.org/polyethylene-foam/where-can-i-buy-closed-cell-foam/feed/ 1 Where can you buy foam that can be cut to custom fit to put mechanical or specific parts in a case or drawer? http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer/ http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer/#comments Thu, 24 Sep 2009 04:07:14 +0000 admin http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer Continue reading →]]> I have to buy it in a store not online.
I want maybe polyethylene or polyurethane.
Here’s what I have in mind if my description wasn’t coherent:

http://www.amcases.com/images/FoamInsert.jpg

http://www.onboard.tv/images/product_images/camera-kit-img01.jpg

http://shashinki.com/shop/images/PLC-1600-BLK.jpg

Try one of those arts and craft stores, here in the western U.S. we have a chain called Michaels. Otherwise ask at a camera shop, photographers use that stuff all the time, they probably could recommend where to buy it

]]> http://www.nrfoam.org/polyethylene-foam/where-can-you-buy-foam-that-can-be-cut-to-custom-fit-to-put-mechanical-or-specific-parts-in-a-case-or-drawer/feed/ 3 can i use RG6 cable to wire my house for freeview, standard freeview,will i get problems.? http://www.nrfoam.org/polyethylene-foam/can-i-use-rg6-cable-to-wire-my-house-for-freeview-standard-freeviewwill-i-get-problems/ http://www.nrfoam.org/polyethylene-foam/can-i-use-rg6-cable-to-wire-my-house-for-freeview-standard-freeviewwill-i-get-problems/#comments Tue, 22 Sep 2009 03:08:04 +0000 admin http://www.nrfoam.org/polyethylene-foam/can-i-use-rg6-cable-to-wire-my-house-for-freeview-standard-freeviewwill-i-get-problems Continue reading →]]> Product Description
RG6 – Coaxial Cable For CATV/CCTV/Satellite

Conductor: 1.02 Bare copper/ Copper Clad Steel
Dielectric: 4.57 mm Foam polyethylene
First Shield: Bonded AL/P
Second Shield: Aluminum wire braid 60% or 90% coverage
Jacket: 6.86 mm black PVC

Certification: UL
Flame Retardant (CM, CMX, CL2, CL2X, CATV, CATVX Type) &UV Resistant is available.

APPLICATION
Used as a distribution cable for indoor CATV, CCTV systems and as a connection cable for satellite systems where lower attenuation required.

if its for using of arial cable to freeview boxes then yes rg6 cable is perfect. it is also great using as a distributor for composite cctv signal

]]> http://www.nrfoam.org/polyethylene-foam/can-i-use-rg6-cable-to-wire-my-house-for-freeview-standard-freeviewwill-i-get-problems/feed/ 2 Can I glue polyurethane products with weldbond? http://www.nrfoam.org/polyethylene-foam/can-i-glue-polyurethane-products-with-weldbond/ http://www.nrfoam.org/polyethylene-foam/can-i-glue-polyurethane-products-with-weldbond/#comments Sun, 20 Sep 2009 01:06:39 +0000 admin http://www.nrfoam.org/polyethylene-foam/can-i-glue-polyurethane-products-with-weldbond Continue reading →]]> I am trying to bond polyurethane plastic sheet to itself and to polyurethane foam. I was told by home depot staff to use weldbond. I would like a second opinion because the first glue they recommended failed miserably and I don’t want to repeat my work for a third time if this is again the wrong glue.

I checked the website and while it specifically excludes polyethylene, unbacked vinyl, PVC, Teflon, polypropylene and vinyl to vinyl; it does not specifically exclude polyurethane. It also does not specifically include it either.

It does say that it will not harm foams and can be used on some plastics.

I appreciate any help people might be able to offer. Thanks in advance and I look forward to reading your responses.
John it is to create an air mattress and must hold it’s seal. It is bonding sheet to sheet and foam to sheet all polyurethane. Bigger plastic would just mean I need trim the plastic. Don’t worry about strength because it will be re-enforced with nylon. It will be exposed to humidity and moisture (from blowing it up) but isn’t expected to be a life raft or anything silly like that.

Most glues have a solvent in them,
look for a polyurethane spray, use it to bond them together,

]]> http://www.nrfoam.org/polyethylene-foam/can-i-glue-polyurethane-products-with-weldbond/feed/ 2