PLA Presentation

8/2/2019 PLA Presentation

1/43

Synthesis of Polylactic acid


2/43

Production

Direct condensation of lactic acid single step

Ring opening polymerization- Multi step process


3/43

Feasible process for the commercial production of PLAby Direct Condensation

Kinetic control over the reaction

Efficient removal of Water : Reletively high temperaturesReduced pressureEntraining agent such as various solvents

Suppresion of Depolymerization

Equilibrium between free acid , Water, and polyesters

Difficulty in removing the trace amount of water in thelate stages of polymerization generally limit the ultimatemolecular weight achievable by this approach

To overcome the above


4/43

Catalysts employed :

Protonic acidsMetalsMetal OxidesMetal halidesOrganic salts of metals


5/43

General properties of Polylacticacid

[CH-C-O]n

O

CH3

Transperancy

Glass Transition temperature 50-600C

Melting Point 130-1800C

Crystallinity : 35-40 %

Tensile Strength : 4-6 Kg/mm2

Elongation : 3-4 %, brittle

Flexural Strength : 9~11 Kg/mm2

Impact Strength :~50 Kg-cm/cm2


6/43

Production of Polylactic acid (PLA) polymer fromcorn sugar replaces petroleum feedstock.

PLA can replace PET, polyesters and polystyrene.

PLA is compostable.

PLA is carbon neutral CO2 is recycled.

In the future, PLA will be made from ligno-cellulosicbiomass.

Bio-Polymer Production

(Cargill-Dow, USA)


7/43

Background on P.L.A.

Used for 30 years in medicine:

Encapsulation of vaccines

Carrier for slow release medication -treatment of prostate cancer and infertility


8/43

A polymer made from cornstarch fermentation, declared anew generic fiber by the US FTC

Competitive in price and performance with fossil fuelderived polymers: PE, PS, PP, polyester

Can be engineered to be biodegradable

Can be used in carpet tiles

Cargill Dow's new facility in Blair, Nebraska, will use up to40,000 bushels of corn each day and can produce morethan 300 million pounds of PLA each year

Polylactic Acid (PLA)


9/43

Click to edit Master subtitle style

Cargill-Dow LLC Plant. Blair, Nebraska. November, 2001. Completed

The School ofPackaging

RAA, 2002Mechanical, Physical and BarrierProperties of Poly(Lactic Acid)

August, 2001 August, 2001

September, 2001

September, 2001


10/43

Main Producers

Producer 2000Million lb/yr*

2001Million lb/yr **

2002Million lb/yr**

Cargill Dow LLC 16 300 300

Mitsui Chemicals 1.3 1.3 1.3

Cost U$S / lb 1.5/2.0 1.0 0.5

* Chemical Week V162, 2000 & Plastics Week, Jan17, 2000


11/43

Polylactic acid (PLA) for plastics production

Co rn

S t a r ch

Un r e f i n ed

Dex t r o s e

Po l yme rP roduc t i onPLA

Lactide

Monome rP roduc t i o n

Lactic Acide rmen t a t i on

Polymer Grades

Fiber

Film

Thermoforming

Bottle

Woven

Non-woven

Etc.

PolymerModificati

on


12/43

Polymerization scheme of copolymersfrom L-lactic acid and D-lactic acid


13/43

Recent development of biodegradablesutures


14/43

Click to edit Master subtitle style

Non-Solvent Process to Prepare PLA

Dextrose

Lactic

Acid

Fermentation

PrepolymerLactide

Formation

Distillatio

n

Disti

llation

Meso

Lactide

Low D

Lactide

PolymerizationPLA

Polymer

UnconvertedPolymer

Cargill Dow LLC Process. Gruber, et. al. 2000.Corn

Coordination / InsertionPropagation

By heating catalyst.


15/43

Biodegradable polymers approvedfor medical applications


16/43


17/43

PGA Polyglycolic acid, PLA Polylactic acid, PLGA Copolymer of PLA & PGA


18/43

Initial cost of PLA was too high that has limited itspackaging applications to high value films, thermoformedcontainers, and coated papers .

PLA has a largest potential market because it is a compostable

and biodegradable thermoplastic.

Derived from annually renewable agricultural resources .

New technologies for mass production of PLA promiseto lower its cost and widen its packaging applications,to include food packaging .

PLA can be fabricated on a variety of familiar processes .

There is a need to better understand its behavior andproperties

to be fully adapted in packaging applications.


19/43

Scheme 1 : Generalized flow sheet for the production of PLA from agricultural waste.


20/43


21/43


22/43


23/43


24/43


25/43


26/43

Synthesis of Polylactic acid over

Solid acid catalyst


27/43

Experimental Section

Lactic acid (LA) is a 85% aqueous solution of the monomer

Catalyst Tungastophosphoric acid H3 [ P(W3O10) 4 ] x H2O (HPA) isheated at 1500C for 3 hours.

The following products were used without any further treatment

Chloroform-d1 with TMS (1%) (deuteration degree not less than 99.5%) fromMerckfor NMR measurements.

Characterization of Polylactic acid :

IR, TGA, DSC 13C NMR and GPC


28/43


29/43

N

2

Experimental set up for the synthesis of polylactic acid

Water removed through dean stark trap

Continuous purging of N2 gas

Dean starktrap


30/43

Infrared Spectral Analysis of PLA

-C=O

O

1759 1092

-C-O


31/43

CDCl3

13C NMR Analysis of PLA


32/43

13C NMR of PLA ( Solvent CDCl3)

169.5 ( 69.0 ( O=C O C H-)

16.6 (

13C NMR Analysis of PLA

C=O )

CDCl3

CH3


33/43

3220

C

Thermo Gravimetric Analysis of PLA

PLA prepared at1500C


34/43


35/43

Thermo Gravimetric Analysis of PLA prepared at 1800C

4000C

PLA prepared at1800C


36/43

Gel Permeation Chromatography Analysis

Wt Molecular weight -42496

Polymerization of lactic acid by using various catalysts


37/43

Polymerization of lactic acid by using various catalysts


38/43

Catalyst Temperature

(0C)

Mw(g/mol)

GPC

H2SO4*(Conventional)

HPW#

180200

220

150

3100030600

32600

42496

Comparison with conventional catalyst

* reaction duration -12h# reaction duration -3 h


39/43

Table 1 Summary of the catalysts used for polymerization of Lactic acidCondensation polymerization

S.No

Catalyst Weight % of catalysts

Temp K MW(g/mol)

123456

Tolune sulphonic acidSulphuric acidBoric acidPhosphoric acidNafion-HMethyl sulphonic acid

1,2.50.1to 1.5,2.510.1,2.52.02.5

373-423,403373,403358-393453,473,433403

145810000031000,650003800,6500400020000

Ringopening polymerization


40/43

Ringopening polymerization

123456

78910111213141516

171819202122232425

26272829303132

ZnCl2Al(acac)Sn(II)octoateSb2O3Ti(IV)butylateTi(IV)isopropylate

Dibutyltin dilaurate (DBTL)Stannous octoateTetraphenyltinStannous octoateMgAlZnSnTiO2ZnO

GeO2ZrO2SnOSnCl2SnCl4Mn(AcO)2Fe2(LA)3Co(AcO)2

Ni (AcO)2

Cu (AcO)2Zn(LA)2Y(OA)3Al(iPrO)3Ti (BuO)4TiO(acac)2(Bu)2SnO

0.10.10.10.10.10.1

0.10.05

0.010.50.50.50.50.830.62

0.720.680.570.801.101.571.701.501.51

2.751.862.923.793.552.741.05

353353353353353353

353

451

433433433433433433

433433433403403433433433433

433433433433403403403

47003600800010800150009000

670037000-7600014000-100,00014000-350,0002100540035000230000160020000

13001500230000230000290001900027000320001400000

1900200002000015008000700013000


41/43

Table .2. Typical applications of PLA

Processes End Products

Non woven fibres Personal hygiene, protective clothing, filtration

Oriented films Container labels, tape

Extrusion coatings Dinnerware, food packaging, mulch film

Flexible film Food wrap, trash bags, shrink wrap

Cast sheet Delivery trays

Injection moulding Rigid containers, Dairy containers

foam Clam shells, meat trays


42/43

Developed process utilizes a noncorrosive, environmentally friendlySolid acid catalyst

The reaction temperature is decreased from 1800C to 1500C

The reaction duration is three hours obtained requiredMolecular weight

The solid acid can be completely recovered and regenerated.

The physico-chemical properties of PLA can be widely tunnedaccordingto the requirements i.e by changing various solid acid strength

Salient features


43/43

Documents

PLA Presentation