Electrochromic polymers include conjugated chromophores in spaced relation with one another, and conjugation-break spacers (CBSs). At least one CBS separates adjacent chromophores. The chromophores may be colored in the neutral state, and multicolored to transmissive in different oxidization states.

A novel AB-type copolymer for use in organic photovoltaics. The AB-type copolymer comprises a unit A, where the unit A is ##STR00001##
where R.sub.1 is a carbon chain from about 1 to about 30 units and where Y is selected from CN, F and Cl. The B unit of the AB-type copolymer is selected from is selected from: ##STR00002## ##STR00003##
wherein
X.sub.1, X.sub.2, X.sub.3, and X.sub.4 are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkylthiol, alkoxy, ester, ketone, amide and aryl groups.

A random copolymer comprising the monomer units A and B. In this random copolymer A comprises

##STR00001##

and B comprises

##STR00002##

Additionally, R1 R2, R3 and R4 are side chains independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups. X1 and X2 are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups.

A random copolymer comprising the monomer units A and B. In this random copolymer A comprises

##STR00001##

and B comprises an aryl group. Additionally, R.sub.1 and R.sub.2 are side chains independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups. X1 and X2 are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups.

A random copolymer comprising the monomer units A and B. In this random copolymer A comprises and aryl group and B comprises

##STR00001##

Additionally, R.sub.3 is a side chain independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups.

A random copolymer comprising the monomer units A and B. In this random copolymer A comprises

##STR00001##

and B comprises

##STR00002##

Additionally, R1 R2, R3 and R4 are side chains independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups. X1 and X2 are different and at least one is a Cl and the other is selected from the group consisting of: H, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups.

A random copolymer comprising the monomer unit C and at least two out of the three monomer units A, B, and D. In the random copolymer A comprises

##STR00001##

B comprises

##STR00002##

D comprises

##STR00003##

and C comprises an aryl group. Additionally, R1 R2, R3, R4, R3′, and R4′ are side chains independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups and wherein R3 and R3′ or R4 and R4′ are not equal.

A random copolymer comprising the monomer units A and B. In this random copolymer A comprises

##STR00001##

and B comprises

##STR00002##

Additionally, R1 R2, R3 and R4 are side chains independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups. X1 and X2 are identical and selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups.

The invention relates to novel organic semiconducting (OSC) compounds containing one or more ester-substituted 4,8-dithiophenyl-benzodithiophene units or derivatives thereof, to methods for their preparation and educts or intermediates used therein, to compositions and formulations containing them, to the use of the compounds and compositions as organic semiconductors in, or for the preparation of, organic electronic (OE) devices, especially organic photovoltaic (OPV) devices, perovskite-based solar cell (PSC) devices, organic photodetectors (OPD), organic field effect transistors (OFET) and organic light emitting diodes (OLED), and to OE devices comprising these compounds or compositions.

Various photocrosslinkable electrochromic polymers are disclosed. The polymers are suitable for an electrochromic layer of an electrochromic device. The polymers are formed with a two-step synthesis method that includes forming a polymer precursor with one or more chromophore blocks, and mixing the polymer precursor with photocrosslinkable monomer units to form the polymer.