CHARACTERISTICS AND REACTIVITY PARAMETERS OF VEOVA™ MONOMERS VV 0.1 Re-issued October 2002 Monomer characteristics
VEOVA Monomer 9, VEOVA Monomer 10 and VEOVA Monomer 11 reprent a family of vinyl ester monomers with a unique highly branched carbon-rich structure (Figure 1). Their principal u is as modifying comonomers in vinyl and acrylic polymerisation. Typical properties and specifications are listed in their product data sheets.
VEOVA 9, 10 and 11 are monomers with many similarities. Their main characteristics are as follows:
• A branched tertiary structure with bulky and hydrophobic hydrocarbon groups (Figure 1). This provides the monomers with a very low surface tension and a hydrophobic nature. As a conquence, the monomers posss a strong resistance to saponification (Figure 2). Furthermore, VEOVA monomers do not degrade under the influence of UV light.
•Reactivity: VEOVA monomers polymeri with various other comonomers through reaction of their vinyl ester functional group. In this way the specific properties of the VEOVA monomers can be imparted to their copolymers.
V INYL E STER of VERSATIC™A CID 9,10,
11
•Similar reactivity to vinyl acetate producing
random copolymers
•Easily copolymerisable with ethylene,
acrylates and methacrylates
•Hydrophobic炸肉的做法
•UV Resistant
•Hydrolytically stable
•Non-Hazardous
Figure 1: Structure of VEOVA monomers where R1 and成人大学报名条件
appreciate用法
R2 are (branched) alkyl groups containing together 6, 7
or 8 carbon atoms for VEOVA 9, 10 and 11 respectively.
Figure 2: Protection of vinyl acetate against hydrolysis by
adjacent VEOVA groups
The various VEOVA monomers mainly differ in the degree of branching and the
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length of the hydrocarbon groups. This leads to differences in the glass
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transition temperature of their homopolymers (Table 1), and conquently to a
different behaviour as modifying comonomers. Whereas VEOVA 9 provides
rigidity to the copolymer, VEOVA 10 is known as a flexibilising comonomer and
VEOVA 11 is an even more efficient flexibilir.
Table 1: Tg of homopolymers of VEOVA.
(ºC) Monomer Tg VEOVA 9 +70
VEOVA 10 -3
VEOVA 11 -40
(Glass transition temperature as described in VEOVA Technical Bulletin 6.1)
Reactivity of VEOVA monomers
VEOVA monomers can be ud with a variety of other monomer types to
produce copolymers. The ea of polymerisation depends on the reactivity ratios
of the monomers ud (Table 2). VEOVA monomers copolymeri very easily
with other vinyl esters, ethylene and most acrylic monomers.
Reactivity of VEOVA monomers with vinyl acetate VEOVA monomers are commonly ud as comonomers for vinyl acetate in emulsion polymerisation, becau they exhibit a similar reactivity (Table 2). During emulsion or solution polymerisation, VEOVA and vinyl acetate are converted at the same rate as illustrated in Figure 3. They can be copolymerid in any desired ratio producing polymers with a random microstructure. This allows the key performance characteristics of VEOVA monomers to be fully exploited. Commonly ud emulsion polymerisation temperatures are in the range of 76 to 80°C, with potassium persulphate as initiator.
Table 2: Reactivity ratios of vinyl ester monomers with other monomer types
Monomer 1 Monomer 2 Temp. (°C) r1 r2 Source
styrene VEOVA 10
VEOVA 10 140
170
25
23
0.04
0.06
2
2
2-ethylhexylmethacrylate VEOVA
曦若10
VEOVA 10 140
170
10.5
3.6
0.08
0.06
2
2
methyl methacrylate vinyl acetate 60 20 0.015 1 ethyl acrylate VEOVA 9 60 6 0.10 2 butyl acrylate ethylene - 13.94 0.01 1
vinyl acetate VEOVA 10
VEOVA 9
ethylene
60
60
130
0.99
0.93
1.02
0.92
0.90
0.97
1
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1
1. Young, Polymer handbook, Chapter II, J. Brandrub, E.H. Immergut and W. McDowell,坚信的近义词
Eds., Wiley-Interscience, NewYork, 1975.
Figure 3: Vinyl acetate and VEOVA 10 instantaneous monomer conversion determined by Gas Chromatography during a mi-continuous emulsion polymerisation process.
Reactivity of VEOVA monomers with (meth)acrylates
VEOVA monomers can be polymerid with acrylate and methacrylate monomers in emulsion, in solution or in bulk. Optimum results are generally obtained by using a mi-continuous process. This
results in a better control of the reactor temperature and in polymers with a more random microstructure.
For emulsion polymerisation, a slightly higher reaction temperature of 85°C is recommended to achieve a more random polymer structure. For solution or bulk polymerisation the best results are obtained at 140°C and above.
Methacrylate monomers can be polymerid with VEOVA monomers in any desired ratio. For acrylate monomers, there are some restrictions in emulsion polymerisation that are further explained in the VEOVA Technical Bulletin VV 2.4 ries.
Reactivity of VEOVA monomers with styrene
VEOVA monomers do not polymeri with styrene in emulsion. Higher temperatures are required to achieve good control over the reaction, and acrylate monomers should be prent to bridge the reactivity differences. Suitable recipes for solution and mass polymerisation at temperature around 160°C are described in parate bulletins.
Handling precautions
For more detailed information on all aspects relating to Health, Safety and Handling, reference should be made to the Safety Data Sheets of VEOVA monomers, which are available from your local Resolution reprentative or distributor. The precautions advid therein should be strictly obrved. For such details related to other products listed in this bulletin, plea contact the suppliers of tho products.
VEOVA and VERSATIC are trademarks of Resolution Performance Products.
The information contained in this publication is to the best of our knowledge, true and accurate, but any recommendations or suggestions which may be made are without guarantee, since the conditions of u are beyond our control. Furthermore, nothing contained herein shall be construed as a recommendation to u any product in conflict with existing patents covering any material or its u.
