Geyser
发表于 2025-3-26 21:50:59
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ENACT
发表于 2025-3-27 01:55:59
Polyurethanes,it is to be noted that in technologically useful polymers of this type the urethane group is not usually the principal group present; other groups such as ester, ether, amide and urea groups are generally contained in the polymer chain in appreciable number.
rheumatology
发表于 2025-3-27 06:20:01
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squander
发表于 2025-3-27 10:44:04
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THROB
发表于 2025-3-27 13:52:09
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是他笨
发表于 2025-3-27 21:41:18
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音乐等
发表于 2025-3-28 00:55:58
Polyamides and related polymers,For the purposes of this chapter, polyamides are defined as polymers which contain recurring amide groups (-CO-NH-) in the main polymer chain.
calamity
发表于 2025-3-28 05:03:44
Silicones,For the purposes of this chapter, silicones are defined as polymers comprising alternate silicon and oxygen atoms in which the silicon atoms are joined to organic groups. The following types of structure come within this definition
minaret
发表于 2025-3-28 07:00:11
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Licentious
发表于 2025-3-28 12:33:30
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