Reactive polymer and hard coating composition

A hard coating composition, comprising:

• a reactive polymer of the following representative formula:
• R4—R3b—NH—CO—R2b—CO—NH—R1—NH—CO—R2a—CO—NH—R3a—R4
• wherein,
• R1 is alkylene, arylene or the combination thereof,
• R2a is —{[O—(CH2)a]b}—O— or —O[—(CH2)d—OOC—(CH2)d—COO]e}—(CH2)d—O—, wherein a is between 2 and 50, b is between 1000 and 2000, d is between 2 and 50 and e is between 1000 and 2000;
• R2b is —{[O—(CH2)h]k}—O— or —O[—(CH2)f—OOC—(CH2)f—COO]g}—(CH2)f—O—, wherein h is between 2 and 50, k is between 1000 and 2000, f is between 2 and 50 and g is between 1000 and 2000, R3a is a cross-linked poly (—Si—O—) group, R3b is a cross-linked poly (—O—Si—) group, and
• R4 is a vinyl functional group;
• an acrylic-type monomer;
• an acrylic-type oligomer;
• and
• a photo initiator.

A method to make a reactive polymer, comprising:

• reacting a compound of formula (17) with an excessive amount of a compound of formula (18) to obtain a compound of formula (20), wherein said compound of formula (17) is
• H—(O—Si)S+1—NH—CO—R2b—CO—NH—R1—NH—CO—R2a—OC—NH—(Si—O)P+1—H,
• R1 is alkylene, arylene or the combination thereof, R2a is —{[O—(CH2)a]b}—O— or —O[—(CH2)d—OOC—(CH2)d—COO]e}—(CH2)d—O—,
• wherein a is between 2 and 50, b is between 1000 and 2000, d is between 2 and 50 and e is between 1000 and 2000, R2b is —{[O—(CH2)h]k}—O— or —O[—(CH2)f—OOC—(CH2)f—COO]g}—(CH2)f—O—, wherein h is between 2 and 50, k is between 1000 and 2000, f is between 2 and 50 and g is between 1000 and 2000, p is between 2 and 50, s is the same as p, (Si—O)P+1 and (O—Si)S+1 respectively represent a cross-linked poly (—Si—O—) group, said compound of formula (18) is
• [AR—(CH2)t—Si—(OR12)3],
• AR is a vinyl functional group, R12 is C1-C10 alkyl, t is between 2-10,
• and
• said compound of formula (20) is
• [AR—(CH2)t—]m(O—Si)S+2—NH—CO—R2b—CO—NH—R1—NH—CO—R2a—OC—NH—(Si—O)P+2—[(CH2)t—AR]n,
• m is between 1 and 10, n is between 1 and 10.