What is PLA?
Polylactic acid (PLA) is a thermoplastic material made from renewable organic resources such as corn starch and sugarcane. Its production relies on biomass resources, which is different from traditional plastic manufacturing methods that rely on fossil fuels. Although the sources of raw materials are different, PLA can be produced using existing plastic processing equipment, which combines environmental protection and cost advantages. This material has physical properties similar to general plastics such as polypropylene (PP) and polyethylene (PE), and also has biodegradable properties, making it an important representative in the field of biobased materials.
What is it used for?
The material properties of PLA make it suitable for the manufacture of plastic film, bottles and biodegradable medical devices, including screws, pins, plates and rods that are designed to biodegrade within 6 to 12 months).
PLA can be used as a shrink-wrap material since it constricts under heat. This ease of melting also makes polylactic acid suitable for 3D printing applications.
However, many types of PLA have a low glass transition temperature, making them unsuitable for making plastic cups designed to hold hot liquids.
Is it Environmentally Friendly?
PLA production uses 65% less energy than producing conventional plastics and generates 68% fewer greenhouse gases and contains no toxins. It can also remain environmentally friendly should the correct end-of-life scenario be followed.
However, the rate of degradation is very slow in ambient temperatures, with a 2017 study showing that there was no degradation seen in over a year of the material being submerged in seawater at 25°C.
However, PLA can be degraded by hydrolysis, thermal degradation or photodegradation:
Hydrolysis: The molecular weight is reduced by cleaving the ester groups of the main chain
Thermal Degradation: This process leads to the appearance of different compounds, such as linear and cyclic oligomers or lighter molecules with different lactide and Mw
Photodegradation: UV radiation causes degradation, particularly where PLA is exposed to sunlight
There are currently four common end-of-life scenarios for PLA:
1. Recycling
This is either chemical or mechanical. Waste material can hold contaminants, but polylactic acid can be chemically recycled using thermal depolymerization or hydrolysis to create a monomer that can then be manufactured into virgin PLA. PLA can also be chemically recycled using transesterification to create methyl lactate.
2. Composting
Industrial composting conditions allow for chemical hydrolysis followed by microbial digestion to degrade the PLA.
3. Incineration
End-of-life PLA can be incinerated, creating 19.5 MJ/kg (8,368 btu/lb) of energy and leaving no residue.
4. Landfill
While PLA can go to landfill, this is the least environmentally friendly option, due to the slow degradation rates of the material in ambient temperatures.
What is PLA pulverizer:
PLA Plastic Pulverizer of the PNMF series is available with disc diameter from 300 to 800 mm. These plastic pulverizer machines are high-speed, precision grinders for the processing of medium-hard, impact-resistant and friable materials. The material to be pulverized is introduced through the center of a vertically fixed grinding disc which is mounted concentrically with an identical high-speed rotating disc. Centrifugal force carries the material through the grinding area and the resulting powder is collected with a blower and cyclone system. Depending on the application the machines can be equipped with one-piece grinding discs or grinding segments.
The plastic pulverizer machine is mainly composed of an electric motor, disc-type blade, feeding fan, vibrating sieve, dust removing system, etc.
According to the customer’s needs, you can choose some accessories, such as a converter, vacuum loader, screw loader, magnetic net, metal separator, chiller, pulse dust collector, metering and weighing packaging machine, etc.
PLA Plastic Pulverizer Video:
PLA pulverizer machine features:
1) PLA pulverizer machine’s overall structure is strong, the overall structure of the machine is compact and strong, can be used permanently.
2) PLA pulverizer machine long service life, wear resistance is stronger than the ordinary mill, the life of the grinding disc is 2 times of the ordinary grinding disc, cost-saving.
3) PLA pulverizer machine is widely used. Due to the unique grinding effect of this mill, it can grind a variety of plastics. Such as PVC, PE, EVA, ABS, LDPE, HDPE, LLDPE, PP, EPS, PS and other plastics.
4) PLA pulverizer machine maintenance is convenient, open the door cover can be cleaned, simple and convenient.
5) PLA pulverizer machine fully automatic operation, automatic feeding, discharging.
6) PLA grinding confidential closed structure, the grinding process is fully enclosed, no dust leakage.
PLA Applications:
Polylactic acid (PLA), as a biobased material, is widely used in medical, food packaging, and consumer manufacturing fields. Its core advantages are reflected in 3D printing: as the preferred material, it supports low-temperature extrusion molding, does not require heating beds or special nozzles, and is compatible with post-processing processes such as polishing and painting. Operation friendly, mechanical performance superior to some engineering plastics, no harmful volatilization during printing, ensuring a safe and odorless working environment. Stable storage, supports multi-color development, can obtain flame retardant, enhanced and other properties through composite modification, suitable for full chain manufacturing from prototype to functional components.
Because PLA can degrade into lactic acid, it can be used for medical implants such as anchors, screws, plates, pins, rods or as a mesh. It breaks down in between 6 months and 2 years, depending on the exact type of material used. This means that these products can gradually transfer a load from a PLA support structure to the body as it heals.
PLA, created with injection moulding, casting or by being spun, is also used as a decomposable packaging material, film or for cups and bags. It is used for compost bags, food packaging, disposable tableware, and loose fill packaging. As a fibre or nonwoven fabric, PLA is used for upholstery, disposable clothing, feminine hygiene products and nappies.