Emulsion Polymers Institute's Annual Short Course:
"Advances in Emulsion Polymerization
and Latex Technology"
Information on the
2010 Short Course
Announcing: The
41st Annual Short Course
"ADVANCES IN EMULSION POLYMERIZATION AND
LATEX TECHNOLOGY"
This is a One-Week Short Course that will be offered by the Emulsion Polymers Institute
(EPI) at Lehigh
University in Bethlehem, Pennsylvania USA on
June 7-11, 2010. Details of the course are given below.
Please note that since the course
lectures are held in a large lecture hall, there are no space
limitations on the number of participants that can register and
attend the course.
COURSE ORGANIZER:
Dr. Mohamed S. El-Aasser
Professor,
Department of Chemical Engineering
Vice President for International Affairs, Lehigh University
For more information, or to request a printed course brochure and
registration form, please contact:
Dr. Eric Daniels, Emulsion Polymers Institute
E-Mail: Eric.Daniels@Lehigh.edu
Phone: (610) 758-3602; Fax: (610) 758-5880
Note: You may also download a registration form
using the links given below to reserve your space in the 2010 Short Course.
Credit cards (Visa, MasterCard or American
Express ONLY) can be used to charge the
course registration fee and University housing fees.
Click
here to download a 2010 Short Course Registration Form in Word (Windows)
format
Click
here to download a 2010 Short Course Registration Form in Rich Text Format (RTF)
(Windows) format
Click
here to download a 2010 Short Course Registration Form in Adobe PDF format
COURSE DESIGN:
The course is an in-depth study of the synthesis, characterization, and properties of
high polymer latexes. The subject matter includes a balance of theory and applications as
well as a balance between chemical and physical problems. Lectures will be given by
leading academic and industrial workers. Lectures will begin with introductory material
and reviews, and will progress through recent research results.
LOCATION AND TIME:
Rauch Business Center
Lehigh University
621 Taylor Street
Bethlehem, Pennsylvania 18015
Lectures will start at 8:30 A.M. Monday to Thursday.
Lectures on Friday will start at 8:00 A.M. and will end by 1:00 P.M.
All Lectures will be held in the
Perella Auditorium in the Rauch Business Center, Room 184
LECTURE/COURSE
SCHEDULE FOR 2009 SHORT COURSE
MONDAY, JUNE 7, 2010
7:00 AM-8:15 AM Continental Breakfast –
Rauch Business Center
8:30 AM-10:00 AM Lecture 1 – Kinetics of Free
Radical-Initiated Polymerization (F. Joseph Schork)
10:00 AM-10:30 AM Coffee
Break
10:30 AM-12:00 PM Lecture 2 – Emulsion
Polymerization Mechanisms and Kinetics
(Gary W. Poehlein)
12:00 PM-1:30 PM Lunch –
Rauch Business Center
291/292/293
1:30 PM-3:00 PM Lecture 3 – The Role of Surfactants in Emulsion
Polymerization Processes (Mohamed S. El-Aasser)
3:00 PM-3:30 PM Coffee
Break
3:30 PM-5:00 PM Lecture
4–
Industrial Uses of Latexes and Preparation of VOC-Free Latexes (Do Ik Lee)
7:00 PM-9:30 PM: Mixer-
Campus Pizza
TUESDAY, JUNE 8, 2010
7:00 AM -8:15 AM Continental Breakfast – Rauch
Business Center
8:30 AM-10:00 AM Lecture 5 – Stabilization
Mechanisms in Aqueous and Non-Aqueous Latexes
(Mohamed S. El-Aasser)
10:00 AM-10:30 AM
Coffee Break
10:30 AM-12:00 PM Lecture 6 –
Engineering of Emulsion Polymerization Reactors
(Gary W. Poehlein)
12:00-1:30 PM Lunch – Rauch Business
Center
1:30 PM- 3:00 PM Lecture 7 –
Semi-Continuous Emulsion Polymerization and Structured Latexes
(Michael F. Cunningham)
3:00-3:30 PM
Coffee Break
3:30-5:00 PM
Lecture 8 – Film Formation and Cohesive Strength Development from
Latex Systems (Andrew Klein)
7:00-8:30 PM Lecture
9
– Question & Answer Session with Short Course Lecturers and Participants (with
most Short Course Speakers)
WEDNESDAY, JUNE 9, 2010
7:00 AM -8:15 AM Continental Breakfast – Rauch
Business Center
8:30-10:00 AM
Lecture 10 – Advances in
Miniemulsion Polymerization (Mohamed S. El-Aasser)
10:00-10:30 AM
Coffee Break
10:30 AM to 12:00 PM Lecture 11 –
Experimental Methods for the Characterization of
Latex Particle
Size and Particle Size Distribution (Cesar A. Silebi)
12:00 PM-1:30 PM Lunch –
Rauch Business Center
1:30-3:00 PM Lecture 12
–
Polyurethane Dispersions (Bedri Erdem)
3:00 PM-3:30 PM Coffee Break
3:30 PM-5:00 PM
Lecture 13
– High Solids Latex Technology (Do Ik Lee)
5:15 PM-7:00 PM: MIXER and Number 14 –
Evening Poster Session – Iacocca Hall, Wood Dining
Room, Mountaintop
Campus
7:00 PM-8:30 PM Banquet
Iacocca Hall, Wood Dining Room, Mountaintop
Campus
THURSDAY JUNE 10, 2010
7:00 AM-8:15 PM Continental Breakfast – Rauch
Business Center
8:30 AM -10:00 AM Lecture 15
–
Living-Controlled Radical Polymerization
in Bulk, Emulsion, and Miniemulsion (Michael F. Cunningham)
10:00 AM-10:30 AM
Coffee Break
10:30 AM - 12:00 PM Lecture
16
– Latex Rheology
(Cesar Silebi)
12:00-1:30 PM Picnic Lunch- Rauch
Business Center Courtyard
1:30 PM-3:00 PM Lecture 17 – Sensors and Control of Emulsion Polymerization Reactors (F. Joseph Schork)
3:00-3:30 PM
Coffee Break
3:30-5:00 PM Lecture 18 – The Structure of
Latex-Bound Pigment Coatings (Do Ik Lee)
FRIDAY, JUNE 11, 2010
6:30 AM -7:45 AM Continental Breakfast – Rauch
Business Center
8:00 AM-9:30 AM Lecture
19 –
Basic Concepts for Morphology Control in Core-Shell Latex Particles (Donald
C. Sundberg)
9:30 AM-9:45 AM Coffee
Break
9:45 AM -11:15 AM
Lecture
20 –
Mechanisms and Examples of
Crosslinking in Latex Systems (Eric S. Daniels)
11:15 AM-11:30 AM Coffee
Break
11:30-1:00 PM Lecture
21 –
Mixing Scale-Up in Emulsion Polymerization (Andrew Klein)
FEES:
The fee structure for the 2010 course includes a variety of
possible discounts as described below (note that discounts cannot be combined).
|
Standard Course Tuition
|
$ 1500 |
|
"Early Bird" Discount (prior to
February 15, 2010) |
$ 1425 |
|
Multiple Participants Discount
(2 or more participants from the same company) |
$ 1350 Each |
|
EPI Industrial Liaison Member
(1st approved participant free) |
$ 0 |
| EPI Liaison Member-
2nd or Subsequent Participants |
$ 1200 Each |
| Graduate Student (needs approval) |
$ 750 |
| 1 Day Registration |
$ 650 |
| 2 Day Registration |
$ 1300 |
Fees cover registration, a set of notes, five (5) days of continental breakfast, four (4) days
luncheon, all breaks, a Pizza Party/Mixer on Monday evening, and a Banquet on
Wednesday evening. Checks payable to
Lehigh University/ Emulsion Polymers Course should accompany applications OR
you may use the downloadable registration forms (links below) to e-mail or Fax
your registration in. An invoice can then be sent to you OR
you may use a credit card to pay for
registration and University housing (Visa, MasterCard or American Express
ONLY). Please
use the downloadable registration form if you would like to charge the course
registration and University housing fees to a credit card. Refund requests received before April
16, 2010 will be
honored in full. A processing charge of $650 will be deducted for cancellations after
April 16, 2010.
Click
here to download a 2010 Short Course Registration Form in Word (Windows)
format
Click
here to download a 2010 Short Course Registration Form in Rich Text Format (RTF)
(Windows) format
Click
here to download a 2010 Short Course Registration Form in Adobe PDF format
PARTICIPANTS:
The course is designed for engineers and scientists who are actively involved in
emulsion work as well as for those who wish to develop expertise in the area. A basic
background in chemistry will be assumed. More advanced and experienced participants may
elect to attend only those days in which material of specific interest is being presented.
All participants will receive a printed set of course notes as well as a CD containing
supplementary course materials in PDF format.
TRANSPORTATION AND LOCALE:
Bethlehem is located in the heart of the Lehigh Valley about 50 miles north of
Philadelphia and 80 miles west of New York City. It is easily accessible by plane via the
Lehigh Valley International Airport (formerly known as the ABE, Allentown-Bethlehem-Easton
Airport), by car via the east-west Route 78 (22) and the north-south Northeast Turnpike
Extension (I-476) and Routes 309 and 378, or by bus from New York City (Port Authority Terminal).
ACCOMMODATIONS:
Modern air-conditioned University dormitories are available within
several blocks of the conference site. Linens are provided. Single occupants will share a
suite (living room and bathroom) with two (2) other course participants.
Each person will have a private bedroom. Please see the following site for a
description of the Campus Square dormitories:
http://www3.lehigh.edu/studentlife/housing/campussq.asp
A processing charge of one night will be deducted for housing
cancellations after April 16, 2010. Telephones are available in every
suite for
your added convenience. Direct-dial local service is available at no charge to you.
AT&T,
MCI, and SPRINT long distance calling cards, or major credit cards are required to make toll calls.
A continental breakfast will be available to course participants at
Rauch Business Center
each morning. Lunches from Monday to Thursday are also included, as is a Pizza
Party on Monday evening and a Banquet on Wednesday evening.
Hotels/motels are for the most part far from campus and will require transportation. Hotel/motel
reservations should be made by contacting the hotel/motel directly.
-
Comfort Suites (*)
120 West Third Street, Bethlehem, PA; 610-882-9700
-
Holiday Inn
Express Hotel & Suites 2201 Cherry Lane, Bethlehem,
PA; 610-838-6110
-
Hampton Inn & Suites at the Gateway
Conference Center, 200 Gateway Drive, Bethlehem, PA; 610-868-2442
-
Best Western Lehigh Valley Hotel and Conference Center, 300
Gateway Drive, Bethlehem, PA; 610-866-5800
-
Historic Hotel Bethlehem,
437 Main Street, Bethlehem, PA; 610-625-5000
-
Hyatt Place, 45 West North Street, Bethlehem, PA 18018;
610-625-0500
- Marriott (Residence Inn,
Courtyard or
Fairfield Inn; Motel Drive,
Bethlehem; 800-321-2211
-
2031 Avenue C, Bethlehem, PA 18017,
610-264-7500
* Only hotel within walking distance of the university.
ABSTRACTS OF COURSE
LECTURES:
MONDAY, JUNE 7, 2010
1. Kinetics of Free Radical-Initiated Polymerization--
F. Joseph Schork (University of Maryland)
A review of the principles of free radical-initiated polymerization,
including the four basic reactions of initiation, propagation, termination and transfer,
inhibition, molecular weight and molecular weight distribution, effect of temperature and
pressure, autoacceleration and diffusion control of termination and propagation, and
copolymerization including copolymerization reactivity ratios and copolymer sequence
distribution.
2. Emulsion Polymerization Mechanisms and Kinetics--
Gary W. Poehlein (Professor Emeritus of Chemical Engineering, Georgia Institute of Technology)
Reaction mechanisms and kinetics of free radical polymerization will
be reviewed. The unique features of emulsion polymerization will be outlined and the
influence of the colloidal size of the reaction sites discussed. Kinetic theories due to
Smith & Ewart, Stockmayer, O'Toole, Roe, Fitch, Ugelstad, and Gilbert will be
discussed.
3. The Role of Surfactants in Emulsion Polymerization Processes--
Mohamed S. El-Aasser (Lehigh University)
Surfactants play major roles during the particle nucleation and
growth stages, with direct impact on latex particle size, size distribution,
polymerization rate, molecular weight, and particle morphology. Surfactants are also
essential during post-polymerization processes: stripping, storage, shipping, and
formulation for several applications. The general characteristics of surfactants and their
adsorption profiles on latex particles will be reviewed. The specific role of surfactants
in determining the particle number according to the various nucleation mechanisms will be
described. Three alternatives to conventional surfactants will be reviewed.
4. Industrial Uses of Latexes and
Preparation of VOC-Free Latexes --
Do Ik Lee (Formerly Senior Scientist in Emulsion Polymers R&D with The DOW Chemical Company)
This talk
will have two parts: “Industrial Uses of Latexes” and “Preparation of VOC-Free
Latexes.”
Industrial
Uses of Latexes: About 10 million metric tons (~20 billion pounds)
of dry latex polymers are being consumed annually in a very large
number of industrial applications, including paints and coatings
(~26% of the total annual latex consumption), paper and paperboard
applications (~24%), adhesives (~23%), carpet backsizing (~10%),
etc. This part of the talk will review the major industrial
applications and types of latexes, and then the important latex
variables affecting the properties of latexes for various
applications will be discussed. Furthermore, industrial latexes will
be grouped in terms of their Tg ranges for various
applications which are in turn grouped in terms of filler levels.
Finally, some specific applications will be highlighted and their
latex requirements and future needs will be discussed.
Preparation
of VOC-Free Latexes: Historically, butadiene-containing copolymer
latexes, such as gel-free SBR (styrene butadiene rubber) and
crosslinked S/B latexes, have been steam stripped to remove their
residual monomers, whereas the residual monomers of non-gel forming
polymer latexes, such as acrylic latexes, have been burned out
(i.e., cooked down) in their post-polymerization steps by using
organic peroxides and reducing agents known as “chaser catalysts” in
the industry. However, public demands and government regulations for
ever lower amounts of residual monomers and VOC’s contained in
latexes and latex-containing coating formulations may require the
industry to consider many different approaches to meet the
challenges. For example, in some cases where the post-polymerization
burnout alone may not be sufficient to meet the demands, the burnout
approach must be either combined with or entirely switched to steam
stripping or other approaches. This part of talk will discuss the
mechanisms for both batch and continuous steam stripping processes,
the post-polymerization burnout mechanisms, various initiator
systems for the burnout, and other considerations.
TUESDAY, JUNE 8, 2010
5. Stabilization Mechanisms in Aqueous and Non-Aqueous Latexes--
Mohamed S. El-Aasser (Lehigh University)
The basic concepts and terminology of colloid science will be
introduced. The principles of electrostatic and steric stabilization mechanisms will then
be reviewed. The inverse problem of coagulating and flocculating latexes will also be
discussed.
6. Engineering of Emulsion Polymerization Reactors--
Gary W. Poehlein (Formerly with Georgia Institute of Technology)
The various types of reactors: batch, semi-batch and continuous,
used to produce synthetic latexes, will be reviewed. Pros and cons of various types of
processes will be discussed and theoretical reactor models will be presented where
appropriate. Reactor design and operating factors that influence product properties will
also be reviewed.
7.
Semi-Continuous Emulsion Polymerization and Structured Latexes--
Michael
F. Cunningham (Queen's University)
Semi-continuous (or semi-batch) polymerizations in which the monomer is added
incrementally during the course of reaction are commonly used in industrial
processes because they allow control of the polymerization rate, and because
they can be used to control the particle morphology. “Structured latexes”
are emulsion polymer particles in which the internal morphology and/or
composition vary through the particle. Examples include core-shell particles,
and particles with radial composition gradients between the particle core and
surface. The discussion will describe how semi-continuous processes are run, the
unique features of operating an emulsion polymerization in semi-continuous mode,
and how structured latexes can be synthesized.
8. Film Formation and Cohesive Strength Development from Latex
Systems--
Andrew Klein (Lehigh University)
The cohesive properties of polymer films from latexes are dependent on the film
formation mechanism. Polymer film formation from latex occurs either when: (a) the
molecules from the individual polymer particles interdiffuse and entangle as the particle
boundaries gradually disappear; or, when (b) the molecules partially interpenetrate and
cross-link, forming interparticle "spotwelds"; or when (c) water-soluble
molecules react or interact with functional groups on the particle surface. In the last
two cases, the particle boundaries remain distinct. The role of interpenetration depth and
the diffusion rate on cohesive strength development will be discussed, using model latex
systems.
9. Evening Session: Question and
Answer Session with Most of the Short Course Lecturers and Participants
WEDNESDAY, JUNE 9, 2010
10. Advances in Miniemulsion Polymerization--
Mohamed S. El-Aasser (Lehigh University)
Despite the fact that the first
miniemulsion polymerization was carried out at Lehigh University in 1972, the
term "miniemulsion" was first coined only in 1981. The number of
publications on miniemulsions has been increasing exponentially over the past
decade, including a few patents.
Miniemulsions are relatively stable oil-in-water emulsions with average droplet
diameters ranging from 50 to 500 nm. These are typically prepared using a mixture of
a surfactant and a low molecular weight, highly water-insoluble
costabilizer (sometimes referred to as cosurfactant). In miniemulsion
polymerization, the submicron monomer droplets are the main sites for particle
nucleation and growth via free radical initiation using oil-soluble or
water-soluble initiators. The stability behavior of miniemulsions has been
explained theoretically based on the well know concepts of Ostwald ripening and
thermodynamics. Miniemulsions have been exploited in making new types of polymer
colloids (latexes) that were difficult and sometimes impossible to make using
conventional emulsification or emulsion polymerization processes. These include
preparation of artificial latexes and hybrid latexes, high solids latexes,
polymerization of highly water-insoluble monomers and macromonomers, controlled
polymer microstructure and morphology, encapsulation of pigments and dyes, and
controlled molecular weight via living free radical polymerization. In this
lecture both the theory and practice of miniemulsions will be discussed.
11. Experimental Methods for the Characterization of Latex Particle Size
and Particle Size Distribution --
Cesar A. Silebi (Lehigh University)
The application of fractionation and non-fractionation methods for the
determination of particle size
distribution, the range of applicability, and advantages and disadvantages and
their on-line measurement capability will be discussed.
Among the methods examined are: classical and dynamic light scattering,
sedimentation, disc centrifugation, electrozone sensing, sedimentation field
flow fractionation, capillary hydrodynamic fractionation, and recent advances in
hybrid methods of analysis. Comparisons
of several of these methods will be used to illustrate problems often
encountered in the particle size distribution determination of latexes.
12. Polyurethane Dispersions--
Bedri Erdem (The Dow Chemical Company)
Waterborne polymer systems such
as acrylates and urethanes have emerged to replace solvent-based products in
many demanding applications such as coatings, elastomers, sealants and
adhesives. Not only do these systems result in the preparation of products with
mitigated EH&S issues (solvents, monomers, etc.), but the products produced have
also improved properties and performance.
Aqueous
polyurethane dispersions are heterogeneous compositions where
polyurethane/urea particles are colloidally dispersed in the aqueous
phase by the aid of surface active moieties. The formation and
colloidal stability of submicron size polyurethane particles
(~50-500 nm in diameter) can be obtained by the incorporation of
ionic or nonionic groups into a polymer backbone. Ionic groups such
as carboxylates, sulfonates, or
quarternary ammonium salts are commonly used to incorporate ionic
character into polyurethane polymer backbone.[i]
These functionalities impart water-dispersibility
to the ionomeric resin and help minimize
the requirement for shear which is very critical in the preparation
of PUDs in the batch process. The majority of PUDs produced
commercially (~95%) are from prepolymers having an ionic backbone,
which is attained by incorporating a molecule capable of bearing
ionic (anionic or cationic) charge. Dimethylolpropionic acid (DMPA)
is the most commonly used material to incorporate an internal ionic
moiety for the preparation of anionic prepolymers. The chemistry of
preparing ionic prepolymers is often complex and requires a
fundamental understanding of the process. Several papers have been
published on the preparation of PUDs, but no report was found
describing the details of the prepolymer synthesis.
PUDs based on prepolymers capable of bearing
nonionic and ionic moieties have been produced for a variety of
applications. Therefore, the effects of various parameters on the
kinetics and process of preparing ionic prepolymers were
investigated. The kinetics of the prepolymer synthesis with emphasis
on the disappearance of the acid groups (COOH) was investigated. The
role of the carboxylic acid on the reactions between isocyanate and
polyols were studied in the presence of various variables and
conditions. The effects of the solvent type and amount, prepolymer
composition, presence of different tertiary amines having different
pKa values (triethyl amine, N-methyl morpholine), types of
isocyanate, types of ionic molecules (DMPA, DICAP 600) and their
concentrations on reaction kinetics and storage stability of
prepolymers were studied. The findings enabled the preparation of
anionic prepolymers and submicron size and solvent-free PUDs used
for a variety of applications.
[i] Schriven et al, US Patent 4066591,
PPG; Coogan et al, US Patent: 4801644, ICI; Reiff et
al, US Patent: 4108814, Bayer; Munzmay et al., EP
581159, Bayer; Matsuda et al, US Patent:
4,012,349, 1977; Kim, B.K., Lee,
J.C., J. Polym. Sci, Polym Chem, 34, 1996
(1095) and Erdem, B., Bhattacharjee D., Chen
LJ., A Detailed Understanding of
Polyurethane Dispersions, International Waterborne, High
Solids & Powder Coating Symposium, February 2004, New
Orleans, LA.
13. High Solids Latex Technology--
Do Ik Lee (Formerly with The Dow Chemical Company)
High-solids
latex technology is based on two basic principles: the maximization of latex
particle packing and the minimization of the effective volumes of latex
particles from the viewpoints of dispersion rheology. With these two principles
at hand, the technology is concerned with the maximization of the volume solids
of latexes, while meeting their respective end-use property requirements for a
variety of applications. For this reason, although the technology is capable of
achieving 70% or higher volume solids latexes, its objective is to increase the
volume solids of the existing latexes by 5% to 15% by considering only a bimodal
approach for the packing efficiency. This talk will describe the basic
principles involved in the high-solids dispersion technology, and then discuss
blending (i.e., large and small particle size latex blends) and in-situ (i.e.,
by either surfactant or seed addition during polymerization) methods of
preparation for high-solids bimodal latexes.
14. Advanced Research Topics in Emulsion Polymerization and Latexes: An Evening
Poster Session-- Graduate
Students in the Emulsion Polymers Institute, Lehigh University.
THURSDAY, JUNE 10, 2010
15.
Living-Controlled Radical Polymerization in Bulk, Emulsion, and
Miniemulsion--
Michael
F. Cunningham (Queen's University)
“Living” (or “controlled”) radical
polymerizations provide a novel and potentially inexpensive route to designing
polymers with controlled microstructure (e.g. block copolymers, star polymers)
and narrow molecular weight distributions. While extensive research has been
conducted into homogeneous bulk and solution living radical polymerizations,
investigations into aqueous dispersed phase systems (emulsion and miniemulsion
polymerization) have only recently appeared. Although little progress has been
realized with emulsion polymerization, considerable success has been achieved
using miniemulsion polymerization with living radical systems. This presentation
introduces the three major living radical polymerization chemistries (nitroxide-mediated
radical polymerization (NMRP), atom transfer radical polymerization (ATRP) and
reversible-addition-fragmentation-transfer polymerization (RAFT)), and
summarizes recent progress of these systems in bulk, miniemulsion and emulsion.
The emphasis will be on heterogeneous systems, and more specifically on
those aspects of operating in a heterogeneous environment that influence the
polymerization rate, the molecular weight distribution and the livingness of the
system.
16. Latex Rheology--
Cesar A. Silebi (Lehigh University)
Review
of experimental studies illustrating the various factors that influence the
rheological properties of latexes. Topics to be covered include the effects of
solids concentration, particle size and distribution, electrolyte content,
particle aggregation, adsorbed surfactants, non-spherical particle morphology,
particle swelling, and the use of water-soluble associative and non-associative
polymeric thickeners. Consideration will also be given to thickened latexes and
variables affecting their rheological flow curves.
17. Sensors and Control of Emulsion Polymerization Reactors--
F. Joseph Schork (University of Maryland)
Recent developments in the area of on-line sensors, coupled with the
availability of high-performance digital control systems, have opened up new opportunities
for the efficient operation and control of latex reactors. Available sensors for on-line
analysis will be discussed. The use of such measurements in the application of advanced
control techniques to batch and continuous polymerization reactors will be reviewed, with
special emphasis on controlling the undesirable process dynamics associated with
continuous emulsion polymerization, and optimizing controllers for batch polymerization.
18. The Structure of
Latex-Bound Pigment Coatings--
Do Ik Lee (Formerly with The Dow Chemical Company)
The structure of model
coatings based on monodisperse polystyrene latexes as spherical pigments and
monodisperse, film-forming latexes as binders has been studied to learn more
about the structure of latex-bound pigment coatings: paints and paper coatings.
These model coatings have allowed us to study their structure both theoretically
and experimentally. This study has proposed the formation of coatings as a
two-step process: immobilization and consolidation. The immobilization of model
coatings has been assumed to occur at the random dense packing of plastic
pigment and latex particles, which can be calculated from the theory. Upon
immobilization and further drying, latex particles start to deform and
consolidate the wet coatings into the final dry coatings. From this proposed
two-step process along with three latex shrinkage models, coating porosity, pore
size, number of pores, etc. have been calculated with the knowledge of the
critical pigment volume concentration (CPVC) and plastic pigment particle size.
This study has been extended to latex-bound clay and calcium carbonate pigment
coatings.
FRIDAY, JUNE 11, 2010
19. Basic Concepts for Morphology Control in Core-Shell Latex Particles --
Donald C. Sundberg (University
of New Hampshire)
Structured
latex particles of all sorts of shapes and sizes have been used in a
wide variety of polymer products and are known to impart special
material properties to products ranging from adhesives to
architectural coatings to impact modifiers for brittle plastics.
These particles are usually composed of two or more immiscible, high
molecular weight polymers co-existing in some morphological
arrangement within the latex particles. While the famous
“core-shell” structure is often desired, it may not always be
achievable under the reaction conditions used to create the
composite latex particles. The purpose of this lecture is to
address the fundamental parameters controlling the development of
latex particle morphology and to discuss the effects of common latex
polymerization recipe and process variables on the morphology of the
particles as they emerge from the polymerization reactor. As such
we will introduce the concepts of “thermodynamic equilibrium
morphology” and “kinetically controlled morphology” as distinctively
different approaches to understanding the control of particle
structure. The former is directly related to the interfacial
energies present in the three-phase polymer/polymer/water system and
can be understood by minimizing the total free energy of the system
via the appropriate interfacial tensions. The latter is related to
the competitive rates of oligomeric/polymeric diffusion within the
particle and of chain propagation. It is within the complexities of
simultaneous chain diffusion and propagation that most latex
particles achieve their observable morphologies. Experimental
evidence for a variety of morphologies will be presented with
appropriate scientific analysis.
20. Mechanisms and Examples of Crosslinking in Latex Systems--
Eric S. Daniels (Lehigh University)
The chemistry and technology of crosslinking in latex systems and
their relationship to the latex film formation process and cohesive strength development
in polymer films will be reviewed. Special emphasis will be placed on the crosslinking
mechanisms (homogeneous, interfacial, and interstitial) which arise when a variety of
functional groups such as carboxyl, N-methylolacrylamide derivatives, hydroxyl, epoxy, or
isocyanate are incorporated into the latex particles. Research results on
crosslinking and film formation in both conventional and miniemulsion latex systems
containing dimethyl meta-isopropenyl benzyl isocyanate (TMI®) will be
highlighted.
21. Mixing Scale-Up in Emulsion Polymerization--
Andrew Klein (Lehigh University)
Scale-up of the mixing process in emulsion polymerization involves
breaking the process down into individual but interrelated steps. The effect of mixing on
the microscopic heterogeneity of the continuous phase, fluid shear rates and heat transfer
allows each to be considered separately. A few of these effects will be discussed and
illustrated with specific examples. The utility of bench scale experimentation, using an
impeller-modified reaction calorimeter (Mettler RC1), with a view toward scale-up with
some early experimental results, will also be discussed.
LECTURERS:
Michael F. Cunningham--
Associate Professor within the
Department of Chemical Engineering, Queen’s University, Kingston, Ontario,
Canada. He received his Ph.D. in
1990 from the University of Waterloo where he studied chemical engineering with
Prof. K.F. O’Driscoll. Prior to his joining Queen’s University, he was with
the Xerox Research Centre of Canada for six years.
While there he conducted research into the design of composite polymer
particles. He was co-inventor of a
novel composite particle that is now a critical component of the xerographic
developer in Xerox copiers and printers. This work has led to 25 U.S. patents.
Among his research interests are the areas of polymer reaction
engineering, emulsion/miniemulsion polymerization, and living radical
polymerization.
Eric S. Daniels-- Principal Research Scientist and Executive Director,
Emulsion Polymers Institute, Lehigh
University. Received his Ph.D. in Polymer Science and Engineering from Lehigh University
in 1987. Research interests include the biomedical applications of latexes, the mechanism
for the formation of composite latexes, particle morphology, interfacial crosslinking and
film formation in emulsion polymer systems, particle technology, and the role of surfactants in emulsion
polymerization.
Mohamed S. El-Aasser--Vice
President for International Affairs, Lehigh University, and formerly Provost,
Lehigh University; Professor of Chemical Engineering. Ph.D. from
McGill University and Pulp and Paper Research Institute in 1972. Research interests
include emulsion polymerization, emulsification, surface and colloidal properties of
latexes, latex film formation, adsorption from solutions, and stabilization of
colloids.
Bedri Erdem--
Bedri Erdem received his B.Sc. and M.Sc. degrees from the
Department of Chemistry (Polymer and Physical Chemistry) from Karadeniz (Black
Sea) Technical University, Trabzon Turkey. He received his Ph.D. from the
Emulsion Polymers Institute at Lehigh University in January 2000. He joined
Polyurethanes R&D at Dow Chemical Company where he worked contributed and led
the colloids and interfaces programs for waterborne polyurethanes dispersions
and other relevant technologies. He has various roles within the Emulsion
Polymers and Specialty Chemicals business. He has been a Global Application and
Formulation Development Leader in Industrial Coatings within Dow Advance Coating
Materials business. Dr. Erdem has presented numerous papers and has been an
invited speaker in numerous globally-recognized conferences. He has over 30
patent applications (published and in process) and more than 40 publications in
refereed journals and conference publications.
Andrew Klein-- Professor of Chemical Engineering, Lehigh University. Ph.D. in
Chemical Engineering from North Carolina State University at Raleigh. Industrial
experience in emulsion polymers with GAF and National Starch and Chemical Company.
Research interests include colloid and surface chemical aspects of heterogeneous
polymerization kinetics, related thermodynamics, engineering and applications.
Do Ik Lee--
B.
S. degree in Chemical Engineering from
Seoul
National
University
in 1959 and both M. S. and doctoral degrees in Chemical Engineering from
Columbia
University
in 1964 and 1967, respectively. Currently, Adjunct Professor in the Department
of Paper and Printing Science Engineering at Western Michigan University and a TAPPI Fellow. Formerly, Senior
Scientist in Emulsion Polymers R&D at The Dow Chemical Company for 35 years.
His research interests are latex technology, emulsion polymerization, structured
latex polymerization, controlled free-radical emulsion polymerization, solid and
hollow plastic pigments, paper coating technology, paper chemistry, colloid
science, particle packing, dispersion rheology, and associative alkali-soluble
latexes. He holds 28
U.S.
patents.
Gary W. Poehlein--
Professor Emeritus of Chemical Engineering, Georgia
Institute of Technology. Ph.D. in Chemical Engineering from
Purdue
University. Industrial experience with the Procter and Gamble
Company. Research interests include kinetics of emulsion polymerization and
continuous reactor systems.
F. Joseph Schork--
Professor and Chair, Department of Chemical and Biomolecular
Engineering, University of Maryland. Ph.D. in Chemical Engineering from the University of Wisconsin working in the
field of emulsion polymerization reactor dynamics. Industrial experience with E.I. DuPont
de Nemours & Company in the areas of emulsion polymerization and digital process
control. Research interests in polymerization reaction engineering, digital control of
polymerization reactors, system dynamics and nonlinear control. Consultant to various
companies in the area of polymerization reaction engineering.
Cesar A. Silebi-- Professor of Chemical Engineering at Lehigh
University. Ph.D. from Lehigh University. Research interests include particle
separation processes, rheological and colloidal properties of latexes,
multi-component transport in emulsions, and stability of colloidal systems.
Donald C. Sundberg--Dr.
Sundberg has degrees in Chemical Engineering from Worcester
Polytechnic Institute (BSChE) and the University of Delaware (MS and
PhD). After his PhD he worked at the Monsanto Company developing
latex based impact modifiers for ABS polymers, with particular
attention to process technologies at the pilot and plant scale
operations. In 1974 he began an academic career at the University of
Idaho and in 1978 joined the faculty at the University of New
Hampshire (UNH). Throughout the years Don has focused his research
on emulsion polymerization and particularly on the control of
morphology within latex particles.
Dr. Sundberg spent a sabbatical year
at the Institute for Surface Chemistry in Stockholm, Sweden, is a
past Chair of the Gordon Research Conference on Polymer Colloids,
and served as Vice President for Research at UNH for 8 years. He is
now Professor of Materials Science and the Director of the
Nanostructured Polymers Research Center within the Materials Science
Program.