Halogen free and phosphorus free low loss flame retardant compositions containing polycyclic-olefinic polymers with epoxy functionality and melamine

A composition comprising:

• a) melamine;
• b) a polymer blend containing a first polymer having a weight average molecular weight (Mw) of less than 10,000 and a second polymer having a weight average molecular weight (Mw) of at least 60,000;
• wherein said first polymer comprising:
• i) at least one first repeating unit represented by formula (IA), said first repeating unit is derived from a monomer of formula (I):
• wherein:
• denotes a place of bonding with another repeat unit;
• m is an integer 0, 1 or 2;
• wherein at least one of R1, R2, R3 and R4 contains an epoxy group chosen from epoxy, —CH2epoxy, epoxy (C3-C10)cycloalkyl, epoxy (C6-C12) bicycloalkyl, epoxy (C6-C12) aryl and epoxy (C6-C12) aryl (C1-C6)alkyl;
• the remaining R1, R2, R3 and R4 are the same or different and each independently chosen from hydrogen, methyl, ethyl, linear or branched (C3-C16)alkyl, (C3-C10)cycloalkyl, (C6-C12) bicycloalkyl, (C6-C12) aryl and (C6-C12) aryl (C1-C6)alkyl;
• or
• one of R1 and R2 taken together with one of R3 and R4 and the carbon atoms to which they are attached to form a substituted or unsubstituted (C5-C14) cyclic, (C5-C14) bicyclic or (C5-C14)tricyclic ring;
• and
• ii) at least one second repeating unit represented by formula (IIA), said second repeating unit is derived from a monomer of formula (II):
• wherein:
• denotes a place of bonding with another repeat unit;
• n is an integer 0, 1 or 2;
• R5, R6, R7 and R8 are the same or different and each independently chosen from hydrogen, methyl, ethyl, linear or branched (C3-C16)alkyl, (C3-C10)cycloalkyl, (C6-C12) bicycloalkyl, (C6-C12) aryl and (C6-C12) aryl (C1-C6)alkyl;
• or
• one of R5 and R6 taken together with one of R7 and R8 and the carbon atoms to which they are attached to form a substituted or unsubstituted (C5-C14) cyclic, (C5-C14) bicyclic or (C5-C14)tricyclic ring;
• and
• wherein said second polymer comprising:
• iii) at least one third repeating unit represented by formula (IIIA), said third repeating unit is derived from a monomer of formula (III):
• wherein:
• denotes a place of bonding with another repeat unit;
• p is an integer 0, 1 or 2;
• at least one of R9, R10, R11 and R12 is chosen from methylidene, ethylidene, vinyl, linear or branched (C3-C16)alkenyl, (C3-C10)cycloalkenyl, (C6-C12) bicycloalkenyl and (C6-C12) aryl (C2-C16)alkenyl;
• and
• the remaining R5, R6, R7 and R8 are the same or different and each independently chosen from hydrogen, methyl, ethyl, linear or branched (C3-C16)alkyl, (C3-C10)cycloalkyl, (C6-C12) bicycloalkyl, (C6-C12) aryl and (C6-C12) aryl (C1-C6)alkyl;
• or
• one of R5 and R6 taken together with one of R7 and R8 and the carbon atoms to which they are attached to form a substituted or unsubstituted (C5-C14) cyclic, (C5-C14) bicyclic or (C5-C14)tricyclic ring containing at least one double bond;
• and
• iv) at least one fourth repeating unit represented by formula (IA), said first repeating unit is derived from the monomer of formula (I) as defined herein;
• and
• wherein the third repeat unit in the second polymer is present at an amount of at least twenty mole percent based on total moles of third and fourth repeat units;
• c) a crosslinking agent chosen from:
• d) an iron compound chosen from ferric oxide and a compound of formula (IV):
• wherein:
• R is chosen from hydrogen, methyl, ethyl, linear or branched (C3-C16)alkyl, vinyl, linear or branched (C3-C16)alkenyl, (C3-C10)cycloalkyl, (C6-C12) bicycloalkyl, (C6-C12) aryl, (C6-C12) aryl (C1-C6)alkyl, (C2-C16)alkanoyl, di-(C1-C6)alkylamino (C3-C6)alkyl, di-(C1-C6)alkylamino, hydroxy, hydroxy (C1-C6)alkyl, methoxy, ethoxy, linear or branched (C3-C16)alkoxy and (C6-C12) aryloxy;
• e) a tackifier;
• and
• f) one or more additives chosen from a thermal acid generator, a free radical initiator, an antioxidant, a synergist and a mixture in any combination thereof;
• and
• wherein melamine is present at an amount of at least about 100 parts by weight based on 100 parts by weight of the polymer blend and said composition when formed into a film has a UL-94 rating of at least V-1, a dissipation factor (Df) of less than 0.002 at 10 GHz.