It is a hard plastic and is in the same category as 475.  They are both hard and brittle, but 475 is more durable than PS, which is quite brittle and cracks easily.  PS makes “kiang kiang” sounds when clashed together, and 475 doesn’t really make any loud noises.  However, they are produced from the same material.  PS could be used to make fruit plates and dividers in refrigerators.  If you use PP to make refrigerator dividers, what can you put on it?  The boards would fall off when things are placed on them.  PS is tough and can sustain heavy weight.  If too much weight is put on it, it would just crack.  PS could also withstand coldness, but PP and PE would become too brittle and break if frozen.  Stone powder could be added to PS, PP, and PE, but the portion must be carefully calculated to be within 10%.  PS couldn’t be considered a lonely substance, but it does have limited friends though.  Its best companion is its brother material, 475.  475 could be used to make the inner walls of refrigerators, because it is softer than PS, so it won’t be scratched and broken quite as easily.  PS could be used to make small plant pots, such as the black boxes used for plant shoots.  It is very brittle so can be torn easily.  Clear PS could be sold for 30 NT, and the opaque ones are sold for 13 NT.


PE is usually used to make large barrels, as it doesn’t oxidize easily and is very durable.  It could be recycled for around 10 to 11 NT per kilo.  Previously we mentioned that stone powder could consist for up to 60% in PP, but PE could go up to 80%.  Because PE consists of oily substance, it doesn’t go brittle when stone powder is added; however, PE with 80% stone powder doesn’t really have much use.  PE could be made into photo papers and business cards.  Some business cards now a day could not be torn, it is because of PE’s durability.

When PE clash together, it doesn’t make any sound.  Unless it is on open bucket, and sounds are produced from resonating with the opening.  PP makes louder noises when clashed together. 


PC is hard and can’t be broken, and it could also sustain high heat without burning.  It is also quite heavy, and would require 24 degree salt solution for it to float.  PC is used in making head lights and light sockets for cars.  PC is the priciest, and could be sold for 90 NT per kilo.  It could endure high temperature, and is used in thermos and baby bottles.  PC could withstand over 300 degrees Celsius, and is the most heat resistant of all plastics.  PC has the highest molecular mass, around 2 to 30000; PP is only around 3 to 4000; however, high impact PP has around 6000.  

PC is quite lonely, as it can’t be mixed with others.  It only thinks about itself in life, and can’t get along with others.  The only thing that could accompany PC is ABS, and together, they make alloy.  However, alloy is quite cheap.  Alloy only exists because of the intention to lower the cost of PC.  Motorcycle helmets and the outer shell for motorcycles are made of ABS. 

PC is the most self-center, and PP and PE are most selfless; they could get together with anyone. 

PC makes metal-like sounds when clashed together, because it is quite hard.  PPA also makes metal-like sounds, but it is a rare material.  If you drop a PPA chopstick on the floor, it would make sounds like a metal rod.  If you throw a PPA plate on the ground, it would sound like a metal disk. It’s quite unique and very rare.  It looks like metal and sounds like metal. 

High impact PP

Similar to PP with stone powder and fiber, high impact PP is also made by adding a chemical.  It is targeted to fortifying against high temperature, and because it is higher in density, it could be sold for a good price.  Objects like chairs, toys, buckets are mostly made with high impact PP.  High impact PP has the best market price out of all kinds of PP.  It could be recycled and sold for 16 NT per kilo.  After processing, it could go for 24 NT.  There isn’t a high impact PE.

PP hollow high impact boards could withstand heat and sun, and could be made into boxes and billboards.  Because of the fortification treatment, this substance is hard, durable, and won’t break easily.

PP with stone powder

PP with stone powder added is harder in quality and could be used to make head lights for cars. Because it is hard in consistency, it won’t crack as easily when under impact.  PP with stone powder has the worse market price, 10 to 12 NT per kilo.  If these substances are not recycled by separating into the right category, they would simply just be considered waste dumps.  PP floats in water, but with stone powder added, it will sink.  The amount of stone powder must be of the right portion, because in excess, it would make the material too brittle and would crack easily.  Usually a ratio of 60% of stone powder should work well.  

Original PP

Original PP is melt-blown and fortified to be suitable for containing hot things.  PP is nontoxic.  Of all the plastics, only PP and PE are nontoxic.  Therefore, food containers are usually made of PP and PE.  Meal boxes are made of PP, but stone powder is added to make it harder.  PP could be made into anything, and could be made into high or low densities, which means hard or soft.  High density is made by injection molding, and soft density is by pressing or blowing.  Bottles are usually blown and buckets pressed.  Toys, cups, plates, and others are made by injection molding, and plastic bags are laminated.  Usually toxin could be released from plastics when under heat, but when using PP and PE, these two will not be toxic under moderate heat.  Therefore food containers or household goods are mostly made of PP and PE.  PP is ideal to be recycled and has wide usages, but it could easily oxidize, so can’t be placed under the sun for long.  Bags used at 7-11 are made of PP and break easily; they could be recycled for 4-5 NT per kilo.

PP with fiber

PP with added fiber is very durable and can sustain impact without cracking.  It can also withstand high heat and is usually used for mechanical parts.  With stone powder, PP would crack easily, but it can hold more weight.  With added fiber, it would expand when burned with fire.  PP with fiber has better market value than with stone powder; it goes for 17 to 18 NT per kilo.

However, when recycled, PP with fiber could only be remade into products for PP with fiber.  PP with stone powder could be made into other objects.  With added fiber, it would sink in water; therefore, to distinguish between PP with stone powder or fiber is by placing the object in salted water.  Usually in water with 5 degree of salt, PP with stone powder would float up, but PP with fiber would only float with 7 degree of salty solution.  Most people would test with calcium chloride solution, but that’s made with chemicals and is toxic.  I use nontoxic edible salt.   


Its recent price is around 30 NT, and acrylic has a wide assortment of uses with two production methods of injection and squeeze casting.  The products of injection molding could be recycled to be processed by squeeze casting, and by doing so, an 100 kilo would be compressed into 60 kilos.  On the other hand, recycled squeeze casting materials would garner 95 kilos.  The prices for these two materials are doubled in difference.  Acrylic could be used to make fruit platters, chairs, cabinets, seal chops.  Whatever plastic could be turned into, acrylic could do the same.  It is quite versatile, but also dislikes being with others.  It could be made to look crystal clear, and colors could be added.  Acrylic should only be used to make artsy products to look at, because it is afraid of heat, cold, and is not scratch-resistant.  There is demand for it, but it’s quite hard to recycle.  Usually small pieces are scavenged, unless large store signs are available.    

Acrylic is quite solitary and unfriendly.  It could be made into anything, but not with others.  For example, for injection molding, the pellets produced are done by added heat.  We can’t tell the difference between acrylic and PC pellets, but we just can’t mix them together.  The reason is because of the temperature differences.  Acrylic requires low heat, and will melt if the temperature is too high.  Although it could be made into just about anything, acrylic can’t replace other plastic, because it is too fragile.  In order to keep its clarity, one must be careful when washing it, but scratches are still unavoidable.  It could be shaped into any form, but being so easily scratched, as tail lights, it would become blurry, while others are still clear and bright.  Acrylic is really hard to maintain, but there is a trick I can share with you: you just have to wash it and use cooking oil to polish it, and it will be shiny and bright again. 

Acrylic makes very bright sounds when clashed together.


Water hose, plastic tube, plastic sheathing for electrical wire, plastic floor covering, tape.

Just like PC, PVC could endure high heat, but it is also lonely like PC.  The only substance that PVC could combine with is stone powder.  Raw PVC is divided into hard and soft materials.  Hard PVC is used to make water hose, and soft PVC is used to make plastic tubes, plastic sheathing for electrical wire, rain coat, rain boots, tape, and plastic covering.  Hard and soft PVC could be mixed together to form a medium texture.  The medium PVC could be made into handle bars, handle for brooms, and tubing for diving goggles.  Medium PVC is not ideal for recycling; they could only continue to be used for medium consistency objects.  Hard PVC is quite brittle and cracks when dropped, and soft PVC is durable and can’t be broken; it is quite stubborn.  PVC is the least preferred for recycling, and it is the lowest in price.  Plastic sheathings could be sold for 7 NT, but not many people would take them.  Hoses go for 9 NT, and plastic tubes are 7 NT. 

PVC makes different sounds when produced into different objects.  In tube-shape, it makes loud noises, but as a plate, it barely makes any sound. 


ABS is hard, tough, and could be mixed into 475, AS, and PS, but it would become brittle when combined with them. 

ABS could be made into medicine bottles, helmets, motorcycle outer shells and head light casings.  Almost more than half of a motorcycle is composed of ABS.  ABS can’t be broken easily.  For example, you could throw a medicine bottle as hard as you could, and it wouldn’t crack.  ABS could be sold for quite a good price, and even for mixed colors, it could be sold for 20 NT.   

PC plus ABS will turn into an alloy, and ABS plus AS is still considered an ABS, but it becomes more brittle.  ABS is known to be hard and tough, and very durable.  It makes loud sounds that are similar to PC.  The sound of PC is more of a “kiang” sound, but ABS sounds more like a “ko” sound, and it also doesn’t make any reverberations, unlike that of a PC.  The outer shell of a helmet is made of PC, and if you throw it on the floor, it will make a “tong~~” sound.  The two are pretty close in their hardness, with the only different in sound reverberation, and PC is a bit harder than ABS. 

ABS can’t be considered to be a solitary matter.  PC and PVC are the loneliest ones, and nylon is the friendliest; it could work with anything else.