指導教授:王振乾 教授
學生:林振崑
2010.09.20
Abstract
•聚合反應各參數對粒子的大小（PS）和
顆粒大小分佈（PSD）的影響進行研究。
•例:反應溫度，時間，起始劑濃度和起始劑
的類型，分散劑分子量，包括組成的介質。
Materials
• Monomers: Methyl methacrylate (MMA)
• Initiators: AIBN. ADVN. BPO. KPS
• Dispersants: PAA. PVP
• Dispersed media: Methanol. Water
Polymerization
甲醇/水+PAA or
PVP水溶液
• 在通氮氣下,
100 rmp 機械攪拌
溫度到60度
添加MMA和
溶解於甲醇的
AIBN
反應6小時
Results and discussion
• Effect of polymerization temperature
The size distribution is not much affected
by temperature.
Table 2 shows that a larger particle size
is formed at the higher temperature.
Results and discussion
• Effect of polymerization time
Fig. 1 shows that the resulting
particle size increases gradually,
and size distribution tends to
become more monodisperse
during the polymerization process.
Fig. 1. Relationship between PS, PSD and reaction time: TD60C; MMAD10 wt.% of total;
PAAD10 wt.% of MMA; AIBND1 wt.% of MMA;MeOH:H2OD9:1.
Results and discussion
• Effect of concentration and type of initiator
Fig. 3 shows the effect of AIBN
concentration on the particle
size.
With increasing the initiator
concentration, the particle size
increases and the size distribution
tend to broaden in general, though
in detail the behaviour is complete.
Results and discussion
• Effect of concentration and type of dispersant
In addition, seven representative
dispersants including changes of type
and molecular weight are used in
Table 4.
As illustrated in Fig. 4, the suitable
concentration range of the dispersant
for the preparation of uniform
particles is limited.
Results and discussion
• Effect of media
Varying the weight ratios of
methanol–water mixtures as
dispersed media demonstrates the
relationship between the
solvency of the media and the
particle size (Fig. 5).
Results and discussion
• Effect of media
The curve in Fig. 6 tells us that the
particle size increases in general
and the size distribution remains
monodisperse with increasing
monomer concentration if monomer
concentration is less than 15 wt.%.
Results and discussion
• Effect of electrolyte and crosslinking agent
The results indicate that the particle
size decreases and the size
distribution tends to be broader with
increasing sodium chloride content
due to the change of surface
potentials.
Conclusions
•在甲醇/水的介質中進行分散聚合,得到了
單分散PMMA粒子,大小範圍在1~5 μm .
• PMMA粒子隨聚合溫度,聚合時間,起始劑
濃度,聚合介質,單體濃度增加而增加.
•電解質會減小顆粒大小,但影響不大.