Power law of molecular weight dependence of lateral growth rate of isotactic polypropylene

Polymer ◽  
2006 ◽  
Vol 47 (21) ◽  
pp. 7601-7606 ◽  
Author(s):  
Koji Yamada ◽  
Kaori Watanabe ◽  
Kiyoka Okada ◽  
Akihiko Toda ◽  
Masamichi Hikosaka
Polymer ◽  
1998 ◽  
Vol 39 (19) ◽  
pp. 4535-4539 ◽  
Author(s):  
Motoyuki Okada ◽  
Mutsuo Nishi ◽  
Masato Takahashi ◽  
Hideomi Matsuda ◽  
Akihiko Toda ◽  
...  

Polymer ◽  
1998 ◽  
Vol 39 (8-9) ◽  
pp. 1591-1596 ◽  
Author(s):  
Mutsuo Nishi ◽  
Masamichi Hikosaka ◽  
Akihiko Toda ◽  
Masato Takahashi

2009 ◽  
Vol 257 (10) ◽  
pp. 2175-2181 ◽  
Author(s):  
Miho Kojima ◽  
Fabio Minoru Yamaji ◽  
Hiroyuki Yamamoto ◽  
Masato Yoshida ◽  
Takahisa Nakai

2000 ◽  
Vol 639 ◽  
Author(s):  
H. Shin ◽  
D. B. Thomson ◽  
P. Q. Miraglia ◽  
S. D. Wolter ◽  
R. Schlesser ◽  
...  

ABSTRACTFree-standing single crystals of bulk GaN were grown via unseeded vapor phase transport at 1130°C on hexagonal BN surfaces via direct reaction of Ga with ammonia. The number of nucleation events was reduced and the crystal size increased by introducing the ammonia at high temperatures. The resulting crystals were either needles or platelets depending on the process variables employed. Low V/III ratios achieved via ammonia flow rates ≤ 75sccm and/or ammonia total pressures ≤ 430Torr favored lateral growth. The average lateral growth rate for the platelets was ∼50μm/hr; the average vertical growth rate for the needles was ∼500μm/hr. Growth rates in all other directions for each of these two morphologies were very low. Seeded growth of both needle and platelet crystals was also achieved; however, the growth rate decreased at longer times and higher pressures due to reaction with H2 from the increased decomposition of ammonia. Nitrogen dilution suppressed this decomposition. A 2mm × 1.5mm GaN crystal was grown with minimal decomposition in a 66.7%NH3 and 33.3%N2 gas mixture.


2012 ◽  
Vol 19 (4) ◽  
pp. 28-33 ◽  
Author(s):  
Guo-wei Chang ◽  
Shu-ying Chen ◽  
Qing-chun Li ◽  
Xu-dong Yue ◽  
Guang-can Jin

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