A self-healing, reprocessable and recyclable crosslinked polymer and process for its preparation

A process for recycling a self-healing, reprocessable and recyclable crosslinked polymer comprising units of formula (I)

• wherein
• R4 are radicals independently selected from the group consisting of radicals of formula (II), (III), and (IV):
• R1 and R1′ are radicals independently selected from the group consisting of:
• —H, (C1-C20)alkyl, (C5-C14)aryl, —OR5,—(CO)R6, —O(CO)R7, —(SO)R8, —NH—CO—R9, —COOR10, —NR11R12, —NO2, and halogen;
• R2, R2′, R3, and R3′ are —H;
• P is a polymeric chain,
• *denotes the position through which radical R4 binds to the phenyl ring of the unit of formula (I),
• X is a biradical selected from the group consisting of:
• —CH2—, —O—, —NH—, —S—, —CO—, —S(O2)—, —Si(R13R14)—;
• R5 to R12 are radicals independently selected from the group consisting of:
• —H, (C1-C20)alkyl, and (C5-C14)aryl;
• R13 and R14 are radicals independently selected from the group consisting of (C1-C5)alkyl, and (C5-C14)aryl;
• (C5-C14)aryl radical represents a ring system with 1-3 rings which comprises from 5 to 14 carbon atoms, the rings being saturated, partially unsaturated, or aromatic;
• and being fused, partially fused or isolated;
• being at least one of the rings an aromatic ring;
• and the ring system being optionally substituted by one or more radicals independently selected from the group consisting of (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkoxy, nitro, cyano, and halogen;
• m is from 3 to 4;
• n is from 1 to 2;
• p is from 1 to 2, provided that n+m+p is 6;
• the polymer comprising from 5 to 25 weight % of urea moieties, and having H-bonding and pi-pi staking interactions between the urea groups, and a tensile strength comprised from 3 to 15 MPa, and
• the tensile strength being measured following determined UNE-EN-ISO 527 standard, which comprises the stretching of dumbbell-shaped specimens of normalized dimensions at an elongation rate of 500 mm min−1, ′ and measuring the value of stress (MPa) until the specimen is broken.
• the process comprising the step of applying pressure and heat to the polymer;
• or alternatively,
• a process for recycling a self-healing, reprocessable and recyclable crosslinked polymer comprising units of formula (I)
• wherein
• R4 are radicals independently selected from the group consisting of radicals of formula (II), (III), and (IV):
• R1 and R1′ are radicals independently selected from the group consisting of:
• —H, (C1-C20)alkyl, (C5-C14)aryl, —OR5,—(CO)R6, —O(CO)R7, —(SO)R8, —NH—CO-R9, —COOR10, —NR11R12, —NO2, and halogen;
• R2, R2′, R3, and R3′ are —H;
• P is a polymeric chain,
• *denotes the position through which radical R4 binds to the phenyl ring of the unit of formula (I),
• X is a biradical selected from the group consisting of:
• —CH2—, —O—, —NH—, —S—, —CO—, —S(O2)—, —Si(R13R14)—;
• R5 to R12 are radicals independently selected from the group consisting of:
• —H, (C1-C20)alkyl, and (C5-C14)aryl;
• R13 and R14 are radicals independently selected from the group consisting of (C1-C5)alkyl, and (C5-C14)aryl;
• (C5-C14)aryl radical represents a ring system with 1-3 rings which comprises from 5 to 14 carbon atoms, the rings being saturated, partially unsaturated, or aromatic;
• and being fused, partially fused or isolated;
• being at least one of the rings an aromatic ring;
• and the ring system being optionally substituted by one or more radicals independently selected from the group consisting of (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkoxy, nitro, cyano, and halogen;
• m is from 3 to 4;
• and
• n is from 1 to 2;
• provided that n+m is 5;
• the polymer comprising from 5 to 25 weight % of urea moieties, and having H-bonding and pi-pi staking interactions between the urea groups, and a tensile strength comprised from 3 to 15 MPa, the process comprising the step of applying pressure and heat to the polymer;
• and
• the tensile strength being measured following determined UNE-EN-ISO 527 standard, which comprises the stretching of dumbbell-shaped specimens of normalized dimensions at an elongation rate of 500 mm min−1, ′ and measuring the value of stress (MPa) until the specimen is broken.