- Thanh phan cua chat deo Thanh phdn ciia chdt deo gom:
HS kit hgp voi tim hieu SGK, bay cho biet:
hgp voi tim hieu SGK, bay cho biet: - Khai niem to.
- Dac diem cau tao. - Yeu cau ki thuat cua to.
GV cho HS nghien cim SGK cau HS nhan xet ve:
- Co so phan loai to.
- Cach phan loai, cho vi du.
HS quan sat, nghien ciiu SGK va nhan xet.
- Ta la nhirng vat lieu polime hinh sgi
dai va manh voi do ben nhat dinh.
- Dgc diem cdu tgo: Nhiing phan tir
polime khong phan nhanh, xep song song voi nhau tao thanh to.
- Yeu cdu kl thuat ciia to la tuong doi
ran, tuong doi ben voi nhiet va vdi cac dung moi thong thuong; mem, dai, khong dgc va co kha nang nhugm mau. 2. PHAN LOAI
va yeu HS nghien ciiu SGK va nhan xet. - Dua vao nguon goc de phan loai to. - To dugc chia lam hai loai:
+ Ta tu nhien (co sin trong .tu nhien)
nhu: Bong, len, to tim,...
+ Ta hoa hoc (che tao bing phuong
phap boa hgc), to boa hgc dugc chia lam hai loai
Hogt dgng cua GV
GV chieu bai tap sau len man hinh cho HS thao luan.
Dieu nao sau day khong diing?
A. To tam, bong, len la polime thien nhien.
B. To visco, to axetat la to tong hgp. C. Chat deo la nhung vat lieu bi bien dang duoi tac dung ciia nhiet do va ap suat ma van giii nguyen bien dang do khi thoi tac dung.
Hogt dgng cua HS
Ta tSng hap (chi tao tir polime tong
hgp) nhu to poli amit, to vinylic the...
Ta bdn tSng hap hay ta nhdn tgo (xuit
phat tir polime thien nhien nhung dugc che biln them bing phuong phap hoa hgc) nhu to visco, to xenlulozo axetat...
HS quan sat va nhan xet
Dap an B
Hogt dgng 5
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