Formable cellulosic

material for packaging Overview of the FuBio JR2 WP4 Task 2

FIBIC Seminar 27.8.2013

29.8.2013 FuBio Seminar

Elias Retulainen VTT Technical Research Centre of Finland

FuBio JR2 29.8.2013 Presenter

Research partners

• Aalto University – Janne Laine & Alexey Khakalo

• Åbo Akademi – Pedro Fardim & Jasmina Obradovic

• LUT – Henry Lindell & Panu Tanninen

• VTT – Elias Retulainen , Alexey Vishtal, Erkki Salo, Pirjo Heikkilä

Fibre based products of future

replacement of oil-based

materials with fibre based

materials

new shapes for paperboard

packaging

new functional properties for

paper based packaging;

modified atmospheric

packaging

new types of packaging lines

Deep drawn shapes, TU Dresden (Hauptmann& Majschak

(2011))

Thermoformed tray, VTT

Objective: To produce fibre-based, web-like material suitable for production of advanced 3D-shapes for packaging i.e. “Moldable Web”

FuBio JR2 29.8.2013 Presenter

Challenge: Failure elongation of fibres and paper is low

Straight single fibres (Jentzen

1964)

Paper made of beaten softwood

fibres (Seth & Page 1981)

The main challenge is due to the fact that cellulose is inherently very stiff, partially crystalline material.

FuBio JR2 29.8.2013 Presenter

Research approaches Fibre

material

Complete or

partial dissolution

of cellulose

Mechanical

modification of

fibres

Modification of

fibre joints

Modification of

fibre network

Electrospinning

DMALiCl and

NaOH-urea

swelling

EmimOAc-

solvent swelling

& dissolution

High-

consistency

treatment

Combined high-

and low-

consistency

treatment

Spray addition

of proteins

Spray and

coating addition

of film-forming

carbohydrates

Compaction of

wet paper

Unrestrained

drying

&

FuBio JR2 29.8.2013 Presenter

Formability testing

Adjustable

packaging line

2D-formability

tester 3D-forming

device Deep-drawing

Air

forming/Vacuum

forming

Formability testing platform

Aims to understand requirements for good formability in different industrial forming processes

Mouldable cellulose

Jasmina Obradovic & Pedro Fardim

Laboratory of Fiber and Cellulose Technology

Åbo Akademi, Turku, Finland

FuBio JR2 WP4 Task 2

Concept of 3D objects prepared by cellulose swelling in DMAc/LiCl solvent system

Use of acrylate epoxidized soybean oil (AESO) as a plasticizer

Another approach using NaOH/urea as a swelling agent for cellulose

X-ray results

Reference pulp

Swelled pulp in DMAc/LiCl

Swelled pulp in DMAc/LiCl and removed solvent

0

100

200

300

400

500

600

700

0 10 20 30 40

Counts

Position 2Ө

Raman results

Reference pulp

Swelled pulp in DMAc/LiCl

Swelled pulp in DMAc/LiCl and removed solvent

Preparation of 3D cellulose objects

previously swelled in DMAc/LiCl solvent

system

RESULTS: AALTO UNIVERSITY Alexey Khakalo & Janne Laine

29.8.2013 FuBio Seminar

40

45

50

55

60

65

70

75

80

85

8

10

12

14

16

18

20

Te

ns

ile

In

de

x, N

m/g

Elo

ng

ati

on

at

bre

ak

, %

Stretch, % Tensile Index, Nm/g

Mechanical properties of cellulose-

gelatin composites

Extensibility increases with the amount of gelatin added, TI is max at 8% addition

10

Grammage 175 g/m2,

Spraying of gelatin solution on prepared paper sheet

before wet pressing, free drying

Calculated masses

for adsorbed gelatin

11

pH 4 pH 10

COOH COO-

NH3+ NH2

pH 4 pH 5.8 pH 10

QCM-D (Wet weight) Thickness

(nm) 7.75 ± 0.05 21.64 ± 0.14 12.77 ± 0.1

Δm (mg/m2) 9.3 ± 0.2 26 ± 0.2 15.3 ± 0.2

SPR (dry weight) Thickness

(nm) 0.3 ± 0.05 1.9 ± 0.1 0.5 ± 0.05

Δm (mg/m2) 0.4 ± 0.05 2.5 ± 0.1 0.65 ± 0.05

Water (%) 95.7 90.4 95.7 0

1

2

3

4

5

6

7

Gelatin pH 4 pH 5.8 pH 10

O/N

ra

tio

Quantifying gelatin

adsorption using XPS

• The adsorption of gelatin to cellulose was found to be highest at isoelectric pH 5.8

• Hydrogen bonding is likely the dominant interaction between cellulose and gelatin

• The adsorbed layer contains a significant amount of coupled water

Topographical changes of gelatin modified

cellulose surfaces

Rq 0.473 nm

Gelatin, pH 4 Gelatin, pH 5,8 Gelatin, pH 10

-1,5

-1

-0,5

0

0,5

1

1,5

2

0 0,5 1

nm

µm

-1,5

-1

-0,5

0

0,5

1

1,5

0 0,5 1

µm

-2

-1,5

-1

-0,5

0

0,5

1

1,5

0 0,5 1

µm

-2

-1,5

-1

-0,5

0

0,5

1

1,5

0 0,5 1

µm

200 nm 200 nm 200 nm 200 nm

Cellulose

Rq 0.764 nm Rq 0.599 nm Rq 0.817 nm

1x1 µm2 AFM height images and corresponding roughness

profiles, tapping-mode 12

RESULTS:VTT Alexey Vishtal & Elias Retulainen

29.8.2013 FuBio Seminar

Combined approach for improved formability

SW Kraft

pulp

High-

consistency

treatment

Low-

consistency

refining

Spraying

with

polymers

Compaction of

fibre web Unrestrained

drying

Ensuring

softening of

polymers in

forming

1. 2.

30% DS,

Wing

defibrator

3.

21-25

SR

,

Valley

beater

4.

1-4%,

carbohydrate,

+optionally

croslinker or

softener

5.

Laboratory

compaction

device, 55-

65% DS

6.

Between two wires,

gap 1-3 mm, Drying

shrinkage up to 15%

7.

Adjusting temperature and

moisture content of paper

in forming.

Extensibility 4%

Extensibility 7-8%

Extensibility 9-11%

Extensibility 12-

15%

Extensibility up to 30%

Improvements in

formability 2-4%-points

Most of these

methods can be

implemented in

industry without

major capital costs

Handsheets

FuBio JR2 29.8.2013 Presenter

Demo shapes & current progress

• The combined approach is a flexible tool to adjust paper to a certain forming process

• Besides formability, other properties can be also improved

• Four sets of the demo-materials were produced at the moment (trays, cups, lids etc.)

• The lab made VTT material have shown superior convertibility to the commercial samples

Sliding Fixed blank

RESULTS: LUT Henry Lindell & Panu Tanninen

29.8.2013 FuBio Seminar

LUT - Adjustable Packaging Line

− A testing platform for evaluating convertability of

barrier coated products with particular

emphasize on die cutting, folding and creasing.

Manufacturing of converting tools was finalized

Q1/2012.

− Test tray used in converting trials was designed

to be relatively demanding to form in order to

obtain differing results between studied materials.

− Test run of FuBio-materials consist of two stages:

− Die cutting of coated paperboard sheets into

tray blanks.

− Press forming of the blanks into trays

− Study of critical steps in converting of biobarrier

materials - insight into creasing and cutting tools

in converting (Q2/2013 )

− Materials are produced by subtask 1.6

(LUT/Backfolk).

FuBio JR2 29.8.2013 Presenter

Summary

• Several approaches have been taken to make formable material from wood fibres and test its formability. The main challenge is due to the fact that cellulose is inherently stiff, partially crystalline material with low elongation potential.

• Possibility of utilization of DMa/LiCl and NaOH/Urea solvent systems for modification of cellulose, and production of 3D-shapes was investigated

• Addition of gelatin can improve elongation of freely-dried paper from 10 to 18% and strength from 55 to 75 Nm/g

• Gelatin was adsorbed by cellulosic fibres irreversibly

• Extensibility as high as 30% was obtained by combining several methods • Requirements for good formability in different forming processes were studied and

evaluated

• Influence of the die-cutting , creasing and pressure forming on the performance of bio-based coatings was evaluated with trays

FuBio JR2 29.8.2013 Presenter

Acknowledgements

The support and assistance of colleagues from the Fubio JR 2 WP4 Task 2 in preparation of this presentation is acknowledged

The support of VTT Graduate school and The International Doctoral Programme in Bioproducts Technology PAPSAT to Alexey Vishtal is acknowledged

Thank You!