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2024年5月7日发(作者：公丽雅)

NatureWorksPLA Polymer 3051D

Injection Molding Process Guide

PLA (polylactide) polymer 3051D, a

NatureWorks LLC product, is de

signed for injection molding

applications where the requirements

are clarity with heat deflection tem

peratures lower than 130ºF (55ºC).

See Table 1 for typical properties.

Melt Temperature

Feed Throat

Feed Temperature

Compression Section

Metering Section

390ºF

70ºF

330ºF

380ºF

400ºF

200ºC

20ºC

165ºC

195ºC

205ºC

Nozzle 400ºF 205ºC

Applications

The variety of products made with

PLA 3051D continues to grow rap

idly. Applications include cutlery,

cups, plates and saucers, and

outdoor novelties. And this is

just the beginning.

Mold 75ºF 25ºC

Screw Speed

Back Pressure

Mold Shrinkage

100-175 rpm

50-100 psi

.004 in/in. +/-.001

3.5-6.9 bar

(1) Note: These are starting points and may need to be optimized. Complete Injection Molding Process Guide available at

(2)

Processing Information

3051D resin can be processed on

conventional injection molding

equipment. The material is stable

in the molten state, provided that

proper drying procedures are fol

lowed. Mold flow is highly dependent

on melt temperature. It is recom

mended to balance screw speed,

back pressure, and process tem

perature to control melt temperature.

Injection speed should be medium to

fast.

Physical Properties

Specific Gravity

Melt Index, g/10 min (210ºC/2.16Kg)

Relative Viscosity

Crystalline Melt Temperature (C)

PLA Resin

(General Purpose)

ASTM

Method

D792

D1238

1.25

10-25

3.0-3.5

150 – 165C D3418

Glass Transition Temperature (C) 55-65 D3417

Mechanical Properties

Tensile Yield Strength, psi (MPa)

Tensile Elongation, %

Notched Izod Impact, ft-lb/in (J/m)

Flexural Strength (MPa)

Flexural Modulus (MPa)

(2) Typical properties; not to be construed as specifications.

Clarity Transparent

7,000 (48)

2.5

0.3 (0.16)

12,000 (83)

555,000 (3828)

D638

D256

D790

Amorphous vs. Crystalline

Pellets*

Crystalline and amorphous pellets

look significantly different. Semi-

Crystalline pellets are opaque and

amorphous pellets are transparent

(See figure below.) Please refer to

drying chart on the following page for

instructions on drying amorphous

PLA pellets.

NatureWorks 3051D is delivered as a

crystalline pellet.

Process Details

(3)

Startup and Shutdown

PLA polymer 3051D is not compatible

with a wide variety of polyolefin

resins, and special purging

sequences should be followed:

1. Clean extruder and bring

temperatures to steady

state with low-viscosity,

general-purpose polysty

rene or polypropylene.

Vacuum out hopper system

to avoid contamination.

Introduce PLA polymer into

the extruder at the operat

ing conditions used in Step

Once PLA polymer has

completely purged the sys

tem, reduce barrel

temperatures to desired set

points.

At shutdown, purge ma

chine with high-viscosity

polystyrene or polypropyl

ene.

(3) Detailed Purging recommendations available at

NatureWorks

PLA Polymer 3051D

Oce Temperature Profile

Drying

In-line drying is recommended for

PLA resins. A moisture content of

less than 0.025% (250 ppm) is

recommended to prevent viscosity

degradation. Polymer is supplied in

foil-lined boxes or bags dried to

<400 ppm when packaged. The

resin should not be exposed to at

mospheric conditions after drying.

Keep the package sealed until ready

to use and promptly dry and reseal

any unused material. The drying

curves for both amorphous and crys

talline resins are shown to the right.

It is important to consider accurate

initial moisture, when calculating

necessary drying time.

Note: Amorphous polymer must

be dried below 120F (50C).

Compostability

Composting is a method of waste

disposal that allows organic mate

rials to be recycled into a product

that can be used as a valuable soil

amendment. PLA is made primarily

of polylactic acid, a repeating chain

of lactic acid, which undergoes a

2-step degradation process. First,

the moisture and heat in the com

post pile attack the PLA polymer

chains and split them apart, creat

ing smaller polymers, and finally,

lactic acid. Microorganisms in

compost and soil consume the

smaller polymer fragments and

lactic acid as nutrients. Since lactic

acid is widely found in nature, a

large number of organisms me

tabolize lactic acid. At a minimum,

fungi and bacteria are involved in

PLA degradation. The end result of

the process is carbon dioxide, wa

ter and also humus, a soil nutrient.

This degradation process is tem

perature and humidity dependent.

Regulatory guidelines and stan

dards for composting revolve

around four basic criteria: Material

Characteristics, Biodegradation,

Disintegration, and Ecotoxicity.

Description of the requirements of

these testing can be found in the

appropriate geographical area:

DIN V 54900-1 (Germany), EN

13432 (EU), ASTM D 6400 (USA),

GreenPla (Japan). This grade of

Natureworks

PLA meets the re

quirements of these four standards

with limitation of maximum layer

thickness of 1650 µm and for coat

ing layers up to 37 µm thick

sections of the Federal Food,

Drug, and Cosmetic Act. The fin

ished polymer is approved for all

food types and B-H use conditions.

We urge all of our customers to

perform GMP (Good Manufactur

ing Procedures) when constructing

a package so that it is suitable for

the end use. Again, for any appli

cation, should you need further

clarification, please do not hesitate

to contact NatureWorks LLC.

European Status

This grade of NatureWorks

PLA

complies with EU Plastics Directive

2002/72/EC, which applies to all

EU member states. The Plastics

Directive is a consolidated version

of the “Monomers Directive (Com

mission Directive 90/128/EEC) and

its first 7 amendments. This

grade of NatureWorks

PLA is also

in compliance with "Bedarfgegen

stände Gesetz", which is the

German implementation of the EU

Plastics Directive 2002/72/EC.

Substances used in the manufac

turing of this product which are not

yet regulated by EU Plastics Direc

tive 2002/72/EC, as amended, are

in compliance with appropriate EU

national regulations. NatureWorks

LLC would like to draw your atten

FDA Status

U.S. Status-

This is to advise you that on Janu

ary 3, 2002 FCN 000178 submitted

by NatureWorks LLC to FDA be

came effective. This effective

notification is part of list currently

maintained on FDA’s website at

/~dms/opa

-. This grade of Nature-

Works

PLA may therefore be

used in food packaging materials

and, as such, is a permitted com

ponent of such materials pursuant

to section 201(s) of the Federal,

Drug, and Cosmetic Act, and Parts

182, 184, and 186 of the Food Ad

ditive Regulations. All additives

and adjuncts contained in the ref

erenced NatureWorks

PLA

formulation meet the applicable

tion to the fact that the EU-

Directive 2002/72/EC, which ap

plies to all EU-Member States,

includes a limit of 10 mg/dm2 of

the overall

migration from finished plastic arti

cles into food. In accordance with

EU-Directive 2002/72/EC the mi

gration should be measured on

finished articles placed into contact

with the foodstuff or appropriate

food simulants for a period and at

a temperature which are chosen

by reference to the contact condi

tions in actual use, according to

the rules laid down in EU-

Directives 93/8/EEC (amending

82/711/EEC) and 85/572/EEC

Please note that it is the responsi

bility of both the manufacturers of

finished food contact articles as

well as the industrial food packers

to make sure that these articles in

their actual use are in compliance

with the imposed specific and

overall migration requirements.

Again, for any application, should

you need further clarification,

please do not hesitate to contact

NatureWorks LLC.

Bulk Storage Recommendations

The resin silos recommended and

used by NatureWorks LLC are de

signed to maintain dry air in the

silo and to be isolated from the

outside air. This design would be

in contrast to an open, vented to

atmosphere system that we under

stand to be a typical polystyrene

resin silo. Key features that are

added to a typical (example: poly

styrene) resin silo to achieve this

objective include a cyclone and

rotary valve loading system and

some pressure vessel relief valves.

The dry air put to the system is

sized to the resin flow rate out of

the silo. Not too much dry air

would be needed and there may

be excess instrument air (-30°F

dew point) available in the plant to

meet the needs for dry air. Our

estimate is 10 scfm for a 20,000

lb/hr rate resin usage. Typically,

resin manufacturers specify alumi

num or stainless steel silos for

their own use and avoid epoxy-

lined steel.

Safety and Handling Considerations

Material Safety Data (MSD) sheets for PLA polymers are

available from NatureWorks LLC. MSD sheets are

provided to help customers satisfy their own handling,

safety, and disposal needs, and those that may be

required by locally applicable health and safety

regulations, such as OSHA (U.S.A.), MAK (Germany), or

WHMIS (Canada). MSD sheets are updated regularly;

therefore, please request and review the most current

MSD sheets before handling or using any product.

The following comments apply only to PLA polymers;

additives and processing aids used in fabrication and

other materials used in finishing steps have their own

safe-use profile and must be investigated separately.

Hazards and Handling Precautions

PLA polymers have a very low degree of toxicity and,

under normal conditions of use, should pose no unusual

problems from incidental ingestion, or eye and skin

contact. However, caution is advised when handling,

storing, using, or disposing of these resins, and good

housekeeping and controlling of dusts are necessary for

safe handling of product. Workers should be protected

from the possibility of contact with molten resin during

fabrication. Handling and fabrication of resins can result

in the generation of vapors and dusts that may cause

irritation to eyes and the upper respiratory tract. In dusty

atmospheres, use an approved dust respirator. Pellets or

beads may present a slipping hazard. Good general

ventilation of the polymer processing area is

recommended. At temperatures exceeding the polymer

melt temperature (typically 170ºC), polymer can release

fumes, which may contain fragments of the polymer,

creating a potential to irritate eyes and mucous

membranes. Good general ventilation should be sufficient

for most conditions. Local exhaust ventilation is recom

mended for melt operations. Use safety glasses if there is

a potential for exposure to particles which could cause

mechanical injury to the eye. If vapor exposure causes

eye discomfort, use a full-face respirator. No other

precautions other than clean, body-covering clothing

should be needed for handling PLA polymers. Use gloves

with insulation for thermal protection when exposure to the

melt is localized.

Combustibility

PLA polymers will burn. Clear to white smoke is produced

when product burns. Toxic fumes are released under

conditions of incomplete combustion. Do not permit dust

to accumulate. Dust layers can be ignited by spontaneous

combustion or other ignition sources. When suspended

in air, dust can pose an explosion hazard. Firefighters

should wear positive-pressure, self-contained breathing

apparatuses and full protective equipment. Water or water

fog is the preferred extinguishing medium. Foam, alcohol-

resistant foam, carbon dioxide or dry chemicals may also

be used. Soak thoroughly with water to cool and prevent

re-ignition.

Disposal

DO NOT DUMP INTO ANY SEWERS, ON THE

GROUND, OR INTO ANY BODY OF WATER. For unused

or uncontaminated material, the preferred options include

recycling into the process or sending to an industrial

composting facility, if available; otherwise, send to an

incinerator or other thermal destruction device. For

used or contaminated material, the disposal options

remain the same, although additional evaluation is

required. (For example, in the U.S.A., see 40 CFR, Part

261, “Identification and Listing of Hazardous Waste.”) All

disposal methods must be in compliance with Federal,

State/Provincial, and local laws and regulations.

NOTICE: No freedom from any patent owned by Nature-

Works LLC or others is to be inferred. Because use

conditions and applicable laws may differ from one loca

tion to another and may change with time, Customer is

responsible for determining whether products and the

information in this document are appropriate for Cus

tomer’s use and for ensuring that Customer’s

workplace and disposal practices are in compliance with

applicable laws and other governmental enactments.

NatureWorks LLC assumes no obligation or liability for the

information in

this document. NO WARRANTIES ARE GIVEN; ALL

IMPLIED WARRANTIES OF MERCHANTABILITY OR

FITNESS FOR A PARTICULAR USE ARE EXPRESSLY

EXCLUDED.

Environmental Concerns

Generally speaking, lost pellets are not a problem in

the environment except under unusual circumstances

when they enter the marine environment. They are

benign in terms of their physical environmental impact,

but if ingested by waterfowl or aquatic life, they may

mechanically cause adverse effects. Spills should be

minimized, and they should be cleaned up when they

happen. Plastics should not be discarded into the ocean

or any other body of water.

Product Stewardship

NatureWorks LLC has a fundamental duty to all those

that make and use our products, and for the environment

in which we live. This duty is the basis for our Product

Stewardship philosophy, by which we assess the health

and environmental information on our products and their

intended use, then take appropriate steps to protect the

environment and the health of our employees and the

public.

Customer Notice

NatureWorks LLC encourages its customers and potential

users of its products to review their applications for such

products from the standpoint of human health and

environmental quality. To help ensure our products are

not used in ways for which they were not intended or

tested, our personnel will assist customers in dealing with

ecological and product safety considerations. Your sales

representative can arrange the proper contacts.

NatureWorks LLC literature, including Material Safety Data

sheets, should be consulted prior to the use of the

company’s products. These are available from your Nature

representative.

NOTICE REGARDING PROHIBITED USE

RESTRICTIONS: NatureWorks LLC doeses not recom

mend any of its products, including samples, for use as:

Components of, or packaging for, tobacco products;

Components of products where the end product is in

tended for human or animal consumption; In any

application that is intended for any internal contact with

human body fluids or body tissues; As a critical compo

nent in any medical device that supports or sustains

human life; In any product that is designed specifically for

ingestion or internal use by pregnant women; and in any

application designed specifically to promote or interfere

with human reproduction.

For additional information in the U.S. and

Canada,

call toll-free 1-877-423-7659

In Europe, call 31-(0)35-699-1344

In Japan, call 81-(0)3-3285-0823

15305 Minnetonka Blvd.,

Minnetonka, MN 55345

NatureWorks and the NatureWorks logo are

trademarks of NatureWorks LLC