Plastic sheet for thermoforming
Normally, plastic sheets for thermoforming or vacuum forming can be divided into two main types: plastic sheets for thick-gauge thermoforming and those for thin-gauge thermoforming.
| HDPE plastic sheet | ABS plastic sheet | ABS+TPU plastic sheet |
| PVC plastic sheet | PET plastic sheet | PETG plastic sheet | PS plastic sheet |
Plastic sheets for thick-gauge thermoforming
Commonly used raw material sheets for thick vacuum forming mainly include HDPE, ABS, ABS+TPU, etc. The following is a brief introduction to the basic characteristics of these three types of material.
HDPE plastic sheet for thermoforming
HDPE sheet has good heat resistance, cold resistance, chemical stability, high rigidity, toughness and excellent environmental stress cracking resistance. Main uses: 200-liter buckets, fuel tanks, pallets, large components, yachts, blister tray tops, special packaging for most auto parts, etc. HDPE has more advantages in low temperature resistance, toughness and environmental stress cracking resistance.
ABS plastic sheet for thermoforming
ABS sheet has good impact resistance, heat resistance, low temperature resistance, chemical resistance and excellent electrical properties. Compared with HDPE, it has the characteristics of easy formation, stable product size, good surface gloss, and better load-bearing and compression resistance. Main uses: widely used in automobiles, electronic and electrical, office and communication equipment and other fields. In the field of packaging, it is mainly used in robot automatic pick-up projects that require high packaging dimensional accuracy.
ABS+TPU plastic sheet for thermoforming
ABS+TPU sheet is a new type of board that adds a special co-extrusion process to the ABS board making process to cover the surface of the ABS board with a layer of TPU film. Products using this material have both the excellent mechanical properties of ABS and the high wear and tear resistance of TPU. The cost of this material is 2 to 3 times that of ordinary materials. Because of the high cost, the application of such materials is subject to certain restrictions. TPU features: wear resistance when the material is often subjected to mechanical effects such as friction, scraping, and grinding during use. This will cause its surface to gradually wear away, so the wear resistance of the material is very important. TPU plastic raw material has excellent wear resistance and is more than five times more wear-resistant than natural rubber. It is one of the preferred materials for wear-resistant products. Generally speaking, TPU has high tear resistance, and its tear strength is compared with some commonly used plastics.
Plastic sheets for thin-gauge thermoforming
Commonly used thin blister sheets include: PVC, PET, PP, PS and flocking sheets, gold-plated sheets and anti-static sheets based on them.
PVC plastic sheet for vacuum forming
The most commonly used blister material, PVC sheet, is soft, strong in toughness, and good in plasticity. It can be made into transparent and various colors. Transparent PVC is commonly used to package electronics, cosmetics, toys, gifts and other products.
PET（A-PET）plastic sheet for vacuum forming
APET is hard, has good toughness, high strength, bright surface, environmentally friendly and non-toxic, and is available in transparent and various colors. The disadvantage is that PET high-frequency heat sealing is more difficult and the price is much more expensive than PVC. This material is often replaced by PVC by users who require high-end and environmentally friendly products. PS: low density (light weight), environmentally friendly and non-toxic, very good plasticity, poor toughness and easily brittle. It cannot be made into transparent materials, so it can only be made into bottom-type blister. Because it is easy to crack, this type of blister is not suitable for recycling PP: the material is particularly soft, has good toughness, is environmentally friendly, non-toxic, and is resistant to high temperatures. It is often made into dining utensils. Or the packaging of other high-temperature resistant products; however, its plasticity is poor, processing is difficult, surface gloss is poor, and the color will become lighter during processing.
PET-G plastic sheet for vacuum forming
The physical properties are similar to A-PET, but it can be heat-sealed with high frequency. Its price is 80% more expensive than A-PET.
PS plastic sheet for vacuum forming
PS rigid sheets have low density, poor toughness, and are easy to burn. When burned, they produce styrene gas (a harmful gas), so they are generally used to produce various industrial blister trays.
PET hard sheets have good toughness, high transparency, and are easy to burn. They do not produce harmful gases when burning. They are more environmentally friendly materials, but are more expensive. They are suitable for high-end blister products. Blister blister shells in European and American countries generally require the use of PET hard sheets. However, it is not easy to heat seal, which brings great difficulties to packaging. In order to solve this problem, people compound a layer of PVC film on the surface of PET, named PETG hard sheet, but the price is higher. Rigid PVC is the most widely used plastic. One of the materials. PVC material is an amorphous material. In actual use, PVC materials often add stabilizers, lubricants, auxiliary processing agents, colorants, impact agents and other additives.
PVC material is non-flammable, high-strength, weather-resistant and has excellent geometric stability.
PVC is highly resistant to oxidants, reducing agents and strong acids. However, it can be corroded by concentrated oxidizing acids such as concentrated sulfuric acid and concentrated nitric acid, and is not suitable for situations in which it comes into contact with aromatic hydrocarbons and chlorinated hydrocarbons.
The melting temperature of PVC is a very important process parameter during processing. If this parameter is improper, it will lead to material decomposition problems. The flow characteristics of PVC are quite poor and its process range is very narrow. In particular, PVC materials with large molecular weights are more difficult to process (lubricants are usually added to this material to improve flow characteristics), so PVC materials with small molecular weights are usually used. The shrinkage rate of PVC is quite low, generally 0.2~0.6%