Handbook of Antiblocking, Release, and Slip Additives

388 Pages·2011·4.12 MB·English

by  Wypych

Handbook of
Antiblocking, Release, (cid:3)
and Slip Additives
2nd Edition
George Wypych
Toronto 2011
Published by ChemTec Publishing
38 Earswick Drive, Toronto, Ontario M1E 1C6, Canada
© ChemTec Publishing, 2011
ISBN 978-1-895198-45-4
Cover design: Anita Wypych
All rights reserved. No part of this publication may be repro-
duced, stored or transmitted in any form or by any means with-
out written permission of copyright owner. No responsibility is
assumed by the Author and the Publisher for any injury or/and
damage to persons or properties as a matter of products liabil-
ity, negligence, use, or operation of any methods, product ideas,
or instructions published or suggested in this book.
Library and Archives Canada Cataloguing in Publication
Wypych, George
Handbook of antiblocking, release, and slip additives / George Wypych. -- 2nd
ed.
Includes bibliographical references and index.
ISBN 978-1-895198-45-4
1. Polymers--Additives--Handbooks, manuals, etc. 2. Polymers--Additives--
Health aspects--Handbooks, manuals, etc. I. Title.
TP1142.W964 2011 668.9 C2010-905813-5
Printed in United States and United Kingdom
Table of Contents i
Table of Contents
1 Introduction 1
1.1 Historical developments 1
1.2 Expectations from commercial additives 2
1.3 Definitions 4
1.4 Classification 5
References 6
2 Generic Types 9
2.1 Introduction 9
2.2 Characteristic properties of commercial additives 10
2.2.1 Antiblocking agents 10
2.2.2 Mold release agents 20
2.2.3 Slip agents 25
References 30
3 Standard Methods of Control 33
3.1 Adhesives 33
3.2 Floor coverings 34
3.3 Footwear and walkway surfaces 34
3.4 Geosynthetics 35
3.5 Leather and coated fabrics 35
3.6 Lubricants 36
3.7 Medical 37
3.8 Paints and Coatings 37
3.9 Paper 37
3.10 Plastics and rubber 38
3.11 Roads and pavement 39
3.12 Sport equipment 40
3.13 Textiles 41
References 41
4 Transportation and Storage 47
4.1 Transportation 47
4.2 Storage 48
References 49
5 Mechanisms of Action 51
5.1 Antiblocking agents 51
5.2 Slip agents 57
5.3 Release agents 60
References 65
ii Table of Contents
6 Compatibility and Performance 67
References 71
7 Diffusion and Migration 73
7.1 Diffusion 73
7.2 Distribution of additive in bulk and on surface 76
7.3 How mobility affects additive selection? 78
7.4 Additive transfer to material in contact 79
7.5 Additive loss 80
References 82
8 Interaction with Other Components of Formulation 83
8.1 Fillers 83
8.2 Other components of formulation 85
8.3 Synergy between surface additives 86
8.4 Other properties 88
References 88
9 Processing and Additive Performance 91
References 93
10 Effect on Product Properties 95
10.1 Mechanical properties 95
10.2 Mar and abrasion 97
10.3 Shrinkage and warpage 98
10.4 Blocking force 99
10.5 Adhesion to mold and demolding 101
10.6 Coefficient of friction 105
10.7 Residues on molds 110
10.8 Residues on molded parts 111
10.9 Optical properties 111
10.10 Rheological properties 115
10.11 Electrical properties 118
10.12 Structure and orientation 118
10.13 Thermal aging 119
10.14 UV radiation 121
10.15 Effect on other properties 121
References 124
11 Use in Specific Polymers 127
11.1 ABS 127
11.2 Acrylics 129
11.3 Bromobutyl rubber 131
11.4 Cellulose acetate 132
11.5 Cellulose, acetate, butyrate and propionate 133
11.6 Cellulose nitrate 134
11.7 Chlorinated polyvinylchloride 135
Table of Contents iii
11.8 Chlorosulfonated polyethylene 135
11.9 Copolymers 136
11.10 Cyanoacrylates 139
11.11 Ethyl cellulose 139
11.12 Ethylene-propylene-diene copolymer, EPDM 140
11.13 Ethylene-propylene rubber, EPR 142
11.14 Epoxy resin 143
11.15 Ethylene-vinyl acetate copolymer, EVA 144
11.16 Ionomers 146
11.17 Nitrile rubber 147
11.18 Polyamide 147
11.19 Polybutadiene 148
11.20 Polycarbonate 149
11.21 Polyester 151
11.22 Polyetherimide 154
11.23 Polyethylene 155
11.24 Polyimide 162
11.25 Polylactide 163
11.26 Polymethylmethacrylate 164
11.27 Polyoxymethylene 165
11.28 Poly(N-vinylcarbazole) 166
11.29 Poly(phenylene ether) 167
11.30 Polypropylene 168
11.31 Polystyrene 171
11.32 Polysulfone 173
11.33 Poly(phenylene sulfide) 173
11.34 Polyvinylacetate 174
11.35 Polyvinylalcohol 174
11.36 Polyvinylbutyral 175
11.37 Polyvinylchloride 176
11.38 Polyurethanes 177
11.39 Proteins 181
11.40 Rubber, natural 181
11.41 Silicone 182
11.42 Styrene-butadiene rubber 183
11.43 Styrene-butadiene-styrene 184
11.44 Starch 185
References 185
12 Use in Industrial Products 195
12.1 Adhesives and sealants 195
12.2 Aerospace 197
12.3 Agriculture 198
12.4 Automotive applications 200
iv Table of Contents
12.5 Bottles 202
12.6 Ceramic materials 204
12.7 Composites 205
12.8 Coated fabrics 205
12.9 Cosmetics 207
12.10 Dental materials 207
12.11 Electronics 208
12.12 Fibers 210
12.13 Film 211
12.14 Food 221
12.15 Foams 222
12.16 Gaskets 224
12.17 Inks, varnishes, and lacquers 225
12.18 Medical devices 226
12.19 Membranes 226
12.20 Paints and coatings 227
12.21 Pharmaceutical products 228
12.22 Photographic materials 229
12.23 Pipes 231
12.24 Road construction 232
12.25 Roofing materials 232
12.26 Synthetic paper 233
12.27 Tires 233
12.28 Toys 235
12.29 Wire & cable 235
References 236
13 Various Processing Methods 243
13.1 Blow molding 243
13.2 Calendering 245
13.3 Coextrusion 245
13.4 Compression molding 247
13.5 Compounding (mixing) 250
13.6 Dip coating 251
13.7 Dryblending 253
13.8 Extrusion 255
13.9 Extrusion blow molding 258
13.10 Injection molding 260
13.11 Lithography 263
13.12 Printing 264
13.13 Reaction injection molding 267
13.14 Rotational molding 268
13.15 Rubber processing 269
13.16 Slip casting 271
Table of Contents v
13.17 Thermoforming 271
13.18 Transfer molding 272
References 272
14 Specialized Analytical Methods 277
14.1 Identification 277
14.2 Determination of concentration 278
14.3 Determination of volatility and molecular motion 280
14.4 Study of materials containing additives 281
References 283
15 Mathematical Modelling 287
References 289
16 Health, Safety and Environmental Issues 291
16.1 Antiblocking agents 291
16.1.1 Inorganic 291
16.1.2 Organic 294
16.2 Release agents 294
16.2.1 Fluorocompounds 294
16.2.2 Polydimethylsiloxane 294
16.2.3 Polymeric waxes 295
16.2.4 Other chemical compounds 295
16.3 Slip agents 296
16.3.1 Acids 296
16.3.2 Esters 296
16.3.3 Fatty acid amides 296
16.3.4 Natural wax 297
16.3.5 Salts 297
17 Regulations and Data 299
17.1 Toxic substance control 299
17.2. Carcinogenic effect 301
17.3 Workplace exposure limits 302
17.4 Food regulatory acts 304
References 306
18 Personal Protection 307
18.1 Clothing 307
18.2 Gloves 308
18.3 Eye protection 310
18.4 Respiratory protection 311
References 315
Index 317
1
Introduction
1.1 HISTORICAL DEVELOPMENTS
Surface blocking was a technological hurdle for as long as humans began to pro-
cess materials. In ancient times natural products were used to improve technologi-
cal output and quality. These included beeswax, plant waxes, natural resins, oils,
etc. They were used advantageously in cosmetics (e.g., creams used by Cleopatra
in Egypt), plasters (e.g., wall plasters in Pompei, Italy), molds, etc.
The priority of application of modern additives is not documented in research
publications but the use of antiblocking, release, and slip agents is a rather recent
advancement of technological processes. This is easy to predict, knowing the ori-
gin of several materials involved in their production. Stearic acid is the oldest syn-
thetic material used in material processing. It was first obtained by the French
chemist Chevreul who began studies of soaps and isolated the most common fatty
acids. In 1825, together with Gay-Lussac, Chevreul patented the use of stearic
acid in candle manufacturing. It took about a century to apply stearic acid in poly-
mer processing. Calcium stearate was first used for commercial purposes by Har-
rison in 1924.1
Crambe abyssinica, which is a cool-season oilseed containing large concen-
trations of erucic acid, was introduced in the United States of America in 1940 by
the Connecticut Agricultural Experiment Station.2 About 39% of high-erucic-acid
oils are now used for production of erucamide, which is a common slip agent.2
The first major paper on mold release was published in 1946 by Ziegler.3 It
contained a thorough analysis of the influence of mold material on release proper-
ties. Even more important, the paper3 contained a proposal for a new method of
mold release testing, which gave the fundamental tool for rational analysis of the
problem. More than twenty of the so-called “mold lubricants” were tested by the
newly developed pull-out force method. In addition, the effect of “lubricant” on
product clarity was observed (cid:16) both results being considered in the final selection.
In the best cases, the decrease of up to 80% of pull-out force was obtained with
these tested “lubricants”. Plasticizers and pigments were also found to facilitate
mold release properties in combination with mold release agents.
Film wrapping and handling characteristics were of major concern for film
producers and these prompted studies of slip agents. The first major paper on the
2 1.2 Expectations from commercial additives
improvement of the friction coefficient of polypropylene film was published in
19664 but in the 1950s, studies and inventions were already reported on the sub-
ject. Polymer selection, concentration of fatty acid amide, and its migration to the
film surface were compared with the coefficient of friction of the resultant film.4
Also, in the same period of time, the quality and output of blown film suf-
fered, which led to the first major study on elimination of blocking during produc-
tion of blown film. The study was published in 1967 but some patents had already
been issued in the 1950s.5-7 In this first broader study, various fatty acids were
tested to establish their performance in solving processing problems. In addition
to blocking, the effect of bubble gas (ammonia or air) and the effect of antiblock-
ing agent on film clarity were considered.5
The above shows that the modern machinery gradually being introduced after
the Second World War influenced a search for additives which may contribute to
more efficient production and better quality of materials. Antiblocking, release,
and slip agents are very recent additions to formulations of plastics but very
important for today’s technology.
1.2 EXPECTATIONS FROM COMMERCIAL ADDITIVES
Some literature sources8-15 generalize expectations from these three types of addi-
tive groups. It is interesting to evaluate the list of these expectations as well as to
compare them between the groups to form a base for selection of required prod-
ucts, definition of the groups, and classification of their members. All three
groups affect many similar properties. Their direct comparison will better point to
their differences (Table 1.1).
Table 1.1. Performance indicators and their potential effects on
acceptance of antiblocking (A), release (R), and slip (S) additives
Performance characteristics Effect A R S
Surface roughening8 spacing effect S S N
Particle size distribution8 yield and performance S N N
Specific surface area8 friction coefficient and wear S N N
Dusting13 health S N N
Chemical intertness19 S N N
Density8 product weight S N N
Dispersibility13,14 quality and process time S S S
Number of particles on surface14 efficiency S N N
Homogeneity13 handling Y Y Y
Low moisture pick up13 processing cost, quality Y S S
Purity14 degradation, toxicity Y Y Y
Color15 cost of color correction Y Y Y
Introduction 3
Table 1.1. Performance indicators and their potential effects on
acceptance of antiblocking (A), release (R), and slip (S) additives
Performance characteristics Effect A R S
Haze19 increase with concentration Y Y Y
increase
Compatibility14 optical properties S S S
Refractive index15 clarity, haze S N N
Compatibility with polymer8,19 migration to surface S Y L
Low transfer to material in contact12 migration to coextruded layers S Y Y
Inertness to one contact surface10 ease of separation N Y N
Adhesion to hot metal surface9 demolding temperature, distortion N Y N
Surface tension10 wetting, migration to surface S Y Y
Good spreading characteristics11 formation of film on mold N Y S
Improved mold flow18 lubrication S S Y
Oxidation and thermal stability18 oxygen permeability reduced S Y Y
Weathering18 protective layer S Y Y
Non-interference with polymerization11 properties of product S Y Y
Non-interference with peroxide cure18 composition S S S
Interaction (A and S) synergism or inhibition Y N Y
Residue on product9 adhesion, welding S Y Y
Reduced surface tack18 protective film/surface roughness Y P P
Non-staining18 inert layer on surface, low adhesion S Y Y
Build up10 mold cleaning frequency S Y Y
Non-blooming12 product quality S S Y
Toxicity10 health and safety Y Y Y
Handling safety14 health and safety Y S S
Solvent type and concentration11 health and safety S Y Y
Food contact approval10 health and safety Y Y Y
Low volatility10 loss from melt, bubbling N Y Y
High efficiency11 low concentration required Y Y Y
Wrinkled film waste/cost Y N Y
Increased line speed19 cost Y Y Y
Improvement of production rate15 cost Y Y S
Improved mold filling18 adjustment of melt rheology S S S
Hardness15 equipment wear S N N
Reduced coefficient of friction18 surface film S Y Y
Abrasion and scratch resistance18,19 surface modification S Y Y
Water repellency18 hydrophobic properties S Y Y
Improved electrical properties18 some are antistatics S S S