Chemistry Behind Hair Straightening

Hello Friends I am Soumyaranjan from Odisha and I hope my presentation would be nice and enjoyable. Thank You.

1. Chemistry Behind Hair Straightening
Seminar Presented by
SoumyaranjanPradhan
M.Sc. 1
st
Year (1
st
Semester)
Roll No. 22PGCH001
Departmentof Chemistry
GIETUniversity, Gunupur
Rayagada,Pin-765022

2. CONTENTS
❖Introduction
❖Chemistry behind curly hair
❖Types of Hair Straightening
❖Advantages & Disadvantages
❖Natural way of Hair Straightening
❖Conclusion

3. INTRODUCTION
•Hairisaproteinfilamentandoneofthe
definingcharacteristicsofmammals.
•Therootofhairisknownasbulbandthe
startingpointofhairisknownasFollicle.
•Therearedifferenttypesofhairfolliclesdue
towhichourhairbecomesstraight,wavyand
curly.

4. •Basicallyhumanhairaremadeupofproteinknownas
KeratinsandinthiskeratinsthelargestaminoacidCysteineis
present.
•Cysteine:C
3H
7NO
2S
•CysteinecontainsSulphurgroupsduetowhichsulphur
bridgesorDisulphidebondsareformed.
•StrongBond:Disulphidebond
WeakBond:H-BondandVanderwaalforces
•Becauseofthesetwotypesofbondswehavecurlyhair.
CHEMISTRY BEHIND CURLY HAIR

6. •GenerallytherearetwotypesofHairStraightening.
i.TemporaryHairstraightening(2-4Days)
ii.PermanentHairStraightening(3-4Months)
TYPES OF HAIR STRAIGHTENING

7. TEMPORARY HAIR STRAIGHTENING
•Intemporaryhairstraighteningprocessheat
appliedtohairthroughstraightenerdueto
whichtheweakbondi.e.H-bondbreaksdown
andthisisvalidforonly2-4days.
•Inthisprocessyousuggestedthatdon’thave
towashyourhairbecausewhenwatercontacts
withhairtheH-bondreformedandhairgain
itsoriginalshape.
•Thisislessharmful.

8. PERMANENT HAIR STRAIGHTENING
•In this process Some reducing agents are used to break the strong
bond i.e. Disulphide bond and this is valid for 3-4 months.
•Some examples of reducing agent given below:
i.Ammonium Sulfate
ii.Ammonium Thioglycolate
iii.Sodium Hydroxide
•This is harmful as depending upon the reducing agent used.

10. ADVANTAGES & DISADVANTAGES
Advantages:
•It removes curls & control unwanted volume.
•It straightens and conditions the hair.
•Hair become silky and shiny.
•The only advantage of straightening hair is self-satisfaction.
Disadvantages:
•Hair becomes thin and high maintenance need after straightening.
•Damage original texture and hair fall start.
•High risk of uterine cancer. (US National institutes of health in 17 Oct 2022)
•Itching & Allergic reaction happen.

11. NATURAL WAY OF HAIR STRAIGHTENING
•Aloe Vera
•Lemon juice and coconut oil
•Egg and olive oil
•Castor oil
CONCLUSION
•Ifyoustraightenhairusingahairstraighteningbrush,useaheat
protectoroiltoprotectyourhairfromdamagebeforeusingit.
•Andifyoustraightenyourhairusingchemicals,consulta
dermatologistbeforeusingit.
•Byadoptingthesetwomethods,youcangreatlyreducethelossofyour
hair.

12. Reference:
Raymond Chang Chemistry Book
https://youtu.be/VVj6mpTbcuM
https://youtu.be/LVe3mSMPK-c