摘要
采用化学反应法制备了Ziegler-Natta／有机咪唑盐改性蒙脱土复合催化剂（简称复合催化剂），并通过丙烯单体原位插层聚合制备了聚丙烯-蒙脱土纳米复合材料。考察了n（Al）：n（Ti）、聚合温度、聚合时间及溶剂种类对复合催化剂的活性及定向催化能力的影响。研究结果表明，与商品化CS-2型Ziegler-Natta催化剂相比，复合催化剂的活性明显降低，在n（Al）：n（Ti）=100、聚合温度60℃、聚合时间1h、正庚烷为溶剂时，复合催化剂的活性较高，可达78．4kg／（mol·h）。合成聚丙烯的等规度在85％-97％之间，熔融温度在160℃左右，重均相对分子质量达到（3．6～4．6）×10^5，相对分子质量分布在6．1～6.6之间。溶剂种类对合成聚丙烯的等规度影响较大。
Ziegler-Natta/organically modified montmorillonite （MMT）compound catalyst was prepared chemically. Exfoliated polypropylene （PP）-MMT nanocomposite was synthesized by in-situ interlayer intercalative polymerization. Effects of mole ratio of Al to Ti, polymerization temperature, time and solvent type on catalyst activity and catalytic stereospecificity were studied. Under optimal conditions：n（Al） ： n（Ti）100,60℃ ,1 h and heptane as solvent,activity of compound catalyst is about 78.4 kg/（ mol· h ） ,lower than that of commercial CS-2 Ziegler-Natta catalyst. Isotacticity of PP obtained is in range of 85% - 97% and its melting temperature is about 160 ℃. The weight-average relative molecular mass of the PP can reach （3.6 -4.6）×10^5. Its relative molecular mass distribution is between 6.1 - 6.6. Solvent used greatly affects isotacticity of PP synthesized with compound catalyst.
出处
《石油化工》
CAS
CSCD
北大核心
2006年第9期881-885,共5页
Petrochemical Technology
基金
国家"973"项目(G2003CB615605)
国家自然科学基金项目(5037304850503023)
关键词
丙烯
原位插层聚合
聚丙烯
蒙脱土
纳米复合材料
复合催化剂
propylene
in-situ polymerization
polypropylene
montmorillonite
nanocomposite
compound catalyst
