CC TRNG THI VT L CA POLYMER

TRNG I HC M - A CHT KHOA DU KH

B MN LC HA DU

CC TRNG THI VT L CA POLYMER

1.Kim Thanh H 2.Trn Thy Giang 3. Nguyn Quc Cng 4. Nguyn Minh Giang 5. Nguyn Ngc Cng

Nhm sinh vin thc hin

Gio vin hng dn : PGS.TS.BI TH L THY

NHNG TNH CHT C L C BIT CA POLYME

Nhng trng thi vt l ca polyme s gip ta hiu r hn v polyme

ngha

Ni dung

1

2

S BIN DNG CA POLYME

CC TRNG THI VT L

1 S BIN DNG CA POLYME

1# CC KHI NIM M

U

2# MT S BIN

DNG CA POLYME

1 S BIN DNG CA POLYME

1# CC KHI NIM M

U

2# MT S BIN

DNG CA POLYME

1 1# BIN DNG

L kh nng ca vt th chng li bin dng v phc hi hnh dng ban u khi tc dng

lc bn ngoi .

Phn loi

N HI Hnh dng c

phc hi hon ton.

N HI DO * ch phc hi mt

phn .

*n hi do hay cn gi l n hi nht

1

2# S BIN DNG

BIN DNG THUN NGHCH Phn t bin dang s phc hi li hnh dng ban u

khi ngng tc dng lc bn ngoi . #bin dng n hi

BIN DNG KHNG THUN NGHCH

Phn t gi nguyn c hnh dng bin dng sau khi ngng tc dung lc bn ngoi.

# cht do

3# CHT N HI

Cht kt tinh Thay i hnh dng v bin dng thun nghch khng ln. n hi ca tinh th mang bn cht nng lng.

V khi bin dng th cht c cu trc v nh hnh. Cao su Vt th ch cn mt lc nh bn ngoi tc dng c kh nng bin dng vi trm phn trm.

#nha

M un n hi : c trng cho n hi

=

F : l lc tc dng ln vt th A: Tit din ca mu .

1

4# NG SUT

E : Gi l m un n hi : Bin dng tng i.

Vt liu c bn cht nng lng th c m un n hi ln. Vt liu c bn cht ng hc th c m un nh .

S khc nhau gia hai bn cht l ph thuc vo nhit v hiu ng nhit khi bin dng

1

1 S BIN DNG CA POLYME

1# CC KHI NIM M

U

2# MT S BIN

DNG CA POLYME

1

1

MT S BIN DNG CA POLYME

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3

4

S bin dng do v chy nht

Bin dng n hi cao

Hin tng phc hi

Hin tng tr

1 S BIN DNG DO V CHY NHT

nh ngha l trng hp c bit ca s bin dng d , tng lin tc

khi tc dng mt ng sut tip tuyn khng thay i polymer.

c im Tnh cht ca vt th rn v lng. nht ca dung dch rt cao Kh nng polyme trng ln trong khi ha tan Kh nng th hin rt mnh tnh bt ng hng

M hnh th hin tnh do ca chui polymer

1

1

MT S BIN DNG CA POLYME

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3

4

S bin dng do v chy nht

Bin dng n hi cao

Hin tng phc hi

Hin tng tr

1 BIN DNG N HI CAO

nh ngha l s dui thng ca cc mch di gp khi c lc ngoi v

tr v trng thi khi ct lc

iu kin xut hin Phn t chui polymer cn c un do ln Tc thay i cu dng cn phi cao

1

1 1

1

MT S BIN DNG CA POLYME

2

3

4

S bin dng do v chy nht

Bin dng n hi cao

Hin tng phc hi

Hin tng tr

HIN TNG PHC HI

nh ngha Qu trnh chuyn t trng thi khng cn bng sang trng thi cn bng theo thi gian

Hin tng phc hi

Thay i chp nhong cc gc ha tr v khong cch gia cc nguyn t Vi lc v m-un n hi ln .

S dui thng ca cc phn t gp khc

c im

Ph thuc vo ng sut lc t ,vo thi gian tc dng ca lc. S hi phc ny gi l s hi phc bin dng

1 1

1

MT S BIN DNG CA POLYME

2

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4

S bin dng do v chy nht

Bin dng n hi cao

Hin tng phc hi

Hin tng tr

HIN TNG TR

nh ngha Ngun gc t hin tng hi phc n hi cao khi c lc

tc dng v khi ct lc tc dng ln mu.

Bn cht ca hin tng

S lch nhau v bin dng thun v nghch l do s bin dng pht trin chm hn l s thay i ng sut.

Hai ng bin dng ny khng trng nhau to nn vng tr.

ln vng tr l s khc nhau ca hai din tch OMC v CMD :

S =

+

l ng sut khi tng l ng sut khi gim

2

1

Ni dung

1

2

S BIN DNG CA POLYME

CC TRNG THI VT L

CC TRNG THI VT L

1# TRNG THI T HP V TRNG THI PHA

2# TRNG THI THY TINH HA

3# TRNG THI N HI CAO

4# TRNG THI CHY NHT

5# TRNG THI KT TINH

CC TRNG THI VT L

1# TRNG THI T HP V TRNG THI PHA

2# TRNG THI THY TINH HA

3# TRNG THI N HI CAO

4# TRNG THI CHY NHT

5# TRNG THI KT TINH

TRNG THI T HP

Trng thi kh Dao ng, tim tin v quay, mt t hp nh

Trng thi rn Mt t hp cao, khong cch gia cc phn t nh, khng c s chuyn ng tim tin v quay.

Trng thi lng C tnh cht chuyn ng nh th kh v mt t hp nh th rn

*khc nhau v tnh cht chuyn ng v mt t hp

TRNG THI T HP

Trng thi kh Dao ng, tim tin v quay, mt t hp nh

Trng thi rn Mt t hp cao, khong cch gia cc phn t nh, khng c s chuyn ng tim tin v quay.

Trng thi lng C tnh cht chuyn ng nh th kh v mt t hp nh th rn

*khc nhau v tnh cht chuyn ng v mt t hp

TRNG THI PHA

nh ngha L h khc nhau v b mt phn chia, v nhng tnh cht nhit ng hc.Pha c th d tch ra khi nhau.

Phn loi Pha tinh th: c trng bng bc xa ba chiu ca s phn

b cc nguyn t hay phn t. Pha lng : khng c mng li tinh th, c mt t hp

ging nh l pha tinh th. #pha v nh hnh

Pha kh : chuyn ng hon ton hn n ca cc phn t, ngha l khng c bc no c.

TRNG THI PHA &TRNG THI T HP

GING NHAU Trng thi kh v pha kh

cng nhau. Trng thi rn tng ng

vi hai pha: tinh th v v nh hnh.

Pha lng gm hai trng thi t hp: rn* v lng*.

KHC NHAU Trng thi t hp :nng

lng tng tc v chuyn ng nhit.

Pha : tnh cht nhit ng hc, nh nng lng t do, t khi

rn * dng thy tinh lng * nhit cao hn nhit nng chy.

S CHUYN PHA

nh ngha : S chuyn t trng thi ny sang trng thi khc c lin quan n nhng thay i v hnh thi sp xp ca cc

phn t v thay i tnh cht nhit ng hc

Phn loi

Chuyn pha loi 1: Thay i nhy vt tnh cht nhit ng hc , c trng l thay i entanpy ca h. nhng chuyn pha loi ny nh l : nng chy, kt tinh, ngng t, bay hi . Chuyn pha loi 2: Khng c s thay i nhy vt m thay i t t cc tnh cht nhit ng. khng c n nhit ca s chuyn pha.

NG CONG C NHIT

nh ngha: S ph thuc bin dng vo nhit c xc nh trn my Koncistometer.

Ba vng bin dang c trng cho ba trng thi vt l khc nhau

Vng I : Thy tinh S bin dng rt nh vi ln t l vo nhit gi tr ng sut khng ln, polymer nh l vt rn ch yu tun theo nh lut Hook.

Vng II :n hi cao C s bin dng thun nghch. t thay i vi nhit v c modun n hi khng ln. Bin dng c km theo bin dng chy tng theo nhit .

Vng III : Chy nht Nhit tng lm tng s bin dng khng thun nghch Nhit chuyn t trng thi n hi cao sang chy nht l nhit trung bnh

Ph thuc vo cu trc ca polyme, khi lng phn t, nhit

Trong k thut, phng php c nhit c th dng nghin cu nh hng ca cc cht ph gia khi ng rn polyme.

CC TRNG THI VT L

1# TRNG THI T HP V TRNG THI PHA

2# TRNG THI THY TINH HA

3# TRNG THI N HI CAO

4# TRNG THI CHY NHT

5# TRNG THI KT TINH

1.c tnh ca polyme thy tinh ha

2.S bin dng n hi bt buc

Kh nng thy tinh ha T l nng lng tng tc ni v gia cc phn t vi nng lng

chuyn ng nhit ca cc mt xch polyme.

c im 1.Khi lm lnh mt cht nng chy c th tm thy tinh th hay thy tinh.

2.S chuyn cht lng thnh thy tinh khng phi l s chuyn pha.

3. Vt th thy tinh khc vi th lng : linh ng v trng thi nng lng.

Tnh cht 1.Lin quan cht ch vi un do 2.Khc polyme thy tinh thng l kh nng bin dng gim, tinh gin v n hi tng .

1.c tnh ca polyme thy tinh ha

2.S bin dng n hi bt buc

nh ngha S bin dng ln c pht trin trong trong

polyme thy tinh khi c ng sut ln. Ch xut hin di nh hng ca ng sut ln. C tnh cht thun nghch.

ng sut ti hn th l ng sut t c ln ca nng lng hot ha hay l ng sut m tc bin dng bng

tc phc hi.

Nhit gin Td :nhit m polyme thy tinh mt i kh nng bin dng ln v b ph hy ngay khi c bin dng nh.

Cc yu t ph thuc 1.Cu trc polyme. 2. phn cc : Khng phn cc :Ttt thp. Phn cc mnh :Ttt cao

CC TRNG THI VT L

1# TRNG THI T HP V TRNG THI PHA

2# TRNG THI THY TINH HA

3# TRNG THI N HI CAO

4# TRNG THI CHY NHT

5# TRNG THI KT TINH

c trng cho polyme c un do cao ca phn t. c xem l lng i vi cc mt xch v l thy tinh i vi ton

phn t. Trng thi n hi cao l trng thi khng cn bng.

iu kin xut hin 1# un do phn t polyme ln. 2# Tc thay i hinh dng ca polyme.

Yu t nh hng S thay i cu dng : dao ng hn n dng

lin kt ha hc v chuyn ch ca cc ng phn quay .

Thnh phn ha hc v cu trc phn t. Bn cht lc tng tc, bn cht phn b trt t

cc phn t v nhit .

S ph thuc bin dng n hi cao vo nhit khc nhau ( t1>t2>t3 )

*Xc nh bi s thay i ni nng v entropi i vi s bin dng.

*nng lng t do

BIN DNG N HI CAO & BIN DNG THNG

Nu bin dng chm xc nh ch yu bng thnh phn

entropi.

Nu bin dng nhanh bng

thnh phn ni nng.

CC TRNG THI VT L

1# TRNG THI T HP V TRNG THI PHA

2# TRNG THI THY TINH HA

3# TRNG THI N HI CAO

4# TRNG THI CHY NHT

5# TRNG THI KT TINH

nh ngha L s chuyn ch khng thun nghch ca cc phn t i vi nhau khi c tc dng ca lc ngoi v trong cht hnh

thnh lc ma st ni chng li s chuyn ch ca cc phn t.

Tnh cht S bin dng l khng thun nghch. Tnh chy ca polyme cng cao, mc trng hp cng

thp, nhit cng cao v lng cht thp phn t cng ln.

S chuyn ch mch polyme da trn nng lng hot ha . Nhit hot ha tnh theo s ph thuc nhit ca h s

nht:

lg = lgA +

,.

,.

C CH

c im ca s chy L chuyn ch lin tc Cc mc xch ca mch hay ca nhng phn ca mch . Chng t nhit hot ha khng ph thuc vo chiu di ca mch.

Lun km theo bin dng n hi cao Do dui thng hay gp khc mch.

Ph thuc vo nht nht li ph thuc nhiu vo chiu di mch. Xy ra vi mch un do C cu dng khc nhau ,mch cng xy ra kh khn. Nhit chy nht Ph thuc vo ch bin dng v khi lng phn t.

CC TRNG THI VT L

1# TRNG THI T HP V TRNG THI PHA

2# TRNG THI THY TINH HA

3# TRNG THI N HI CAO

4# TRNG THI CHY NHT

5# TRNG THI KT TINH

C ch qu trnh kt tinh L qu trnh hnh thnh phi (hay mm) ca pha kt tinh trong pha v nh hnh v s ln dn ca cc phi .

Qu trnh kt tinh l s chuyn pha.

Tc kt tinh L lng cht kt tinh trong mt n v thi gian.

Ph thuc vo: 1. Tc to thnh trung tm hay phi kt tinh . 2.Tc ln ca chng.

Note: S kt tinh thng khng bt u nhit nng chy m thp hn.

S kt tinh l s chuyn t bc gn ti bc xa ca cc mch v cc mc xch, ngha l s chuyn pha.Khc vi thy tinh

ha.

YU T NH HNG N KH NNG KT TINH

1 C cu trc mch iu ha ln c kh nng kt tinh Cu trc mch khng iu ha khng c kh nng kt tinh.

2

Nhm phn cc trong phn t, s nh hng d th s kt tinh cng d dng. Tng tc phn t cng ln, nht ca h cng ln tc kt tinh li gim.

3 Chuyn ng nhit ca cc mt xch hay un do mch. Lc ht cc phn t v s chuyn ng nhit ca phn t.

CC TRNG THI VT L

1# TRNG THI T HP V TRNG THI PHA

2# TRNG THI THY TINH HA

3# TRNG THI N HI CAO

4# TRNG THI CHY NHT

5# TRNG THI KT TINH

HT RI

Cm n c v cc bn lng nghe v theo di.