354 化学反应工程与工艺 2010年8月
5 Wessling R A.Polyvinylidene Chloride
.
New York:Gordon&Breach,1977.44
6 Zhou S X,weng Z X,Huang Z M,at a1
.
Phase Partiti。n。f Acryl。nitrile(AN)in VinyI.dene Chl。ride(VDC)/Water System and Its
Effect on VDC-AN Copolymer Composition
.
Chinese J Chem Eng,1999,7(4):326 ̄331
Particle Characteristics of Vinylidene Chloride—Acrylonitrile
Copolymers Prepared by Suspension Polymerization
(1
Xie Jianwu ’ Bao Yongzhon
Department of Chemical and Biologi Engineering,Zheiiang Uni cal
Ver
Zhang Jingtian Huang Zhiming
Engineering,State Key Laboratory of Chemical
sity,Hangzhou 310027,China;
2・Department of Chemical Engineering,Hangzhong Vocational Technology College
,
Hangzh0u 310018,China)
Abstract: Vinylidene chloride(VDC)homopolymer and vinylidene chloride-acrylonitrile(VDC-
AN) copolymers were prepared by suspension polymerization process
, and the influence of AN
content on the particle characteristics and crystallinity of VDC polymers was investigated
.
It was
found that the particles of VDC resins were varied from porous tO compact morpho1ogy with the
increase of mass fraction of AN in polymers
.
When the mass fraction of AN in copolymer was equa1 to
or less than 8.8 ,the internal pore size of VDC-AN copolymer was 0
.
1—2.0“m;when the mass
fraction of AN was equal to or more than 12
.
3 ,the primary particles were coagulated together。the
pore space among the particles was almost disappeared and the VDC~AN copolymer was hardly
crystallized.The increase of AN monomer in VDC-AN copolymers led tO the decrease of crystallinitv
of VDC-AN polymers and the increase of the swelling ability of AN monomer in copolymers
。
which
was the main reason why the structure of VDC and particles became compact
.
Key words: vinylidene chloride;acrylonitrile;suspension polymerization;particle characteristics
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Siluria开发甲烷直接转化制乙烯新型催化剂
美国Siluria技术公司开发出一种纳米级催化剂,它可以在低于常规蒸汽裂解所需的
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贵,天然气资源利用持续增强,我们的目标是将天然气的主要成分甲烷直接转化成化学
工业的基本组成乙烯”。目前,该公司正优化这种催化剂,力争使其适应工业化应用的
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Siluria还表示,这种催化剂也可用于对蒸汽裂解装置进行翻新改造,还可用于其它
反应过程,例如丙烷转化制丙烯,乙烷转化制醋酸等。
李雅丽摘自美CW,2010—7—22