Sprayable hot melt adhesives

A process for spraying blends of propylene copolymers comprising selecting two or more different copolymers independently comprising propylene and up to 50 mole % comonomer, each copolymer independently having:

• an Mw of between 20,000 to 100,000;
• an Mw/Mn of 4 or less:,
• a G″/G′ of 18 or more, when G′ is 10 Pa;
• a Tg of about −5° C. or less;
• a Tm of about 90° C. or less;
• an amorphous content of at least 50%,
• a crystallinity of less than 15%,
• a heat of fusion of at least 5 J/g
• a viscosity of 5000 mPa·sec or less at 190° C.;
• and
• a melting range of less than 75° C.,
• combining the two or more copolymers, and optionally oil, into a blend;
• and atomizing, spiral spraying, oscillation spraying or melt blowing the blend onto a substrate.

A process for atomizing, spiral spraying, oscillation spraying or melt blowing a blend of propylene copolymers onto a substrate comprising selecting two or more different poly-alpha olefin inter-polymers wherein each polymer independently comprises:

• A) from 60 to 94% of units derived propylene and
• B) from 6 to 40 mol % of units derived from one or more of butene, hexene and octene;
• and
• C) optionally from 0 to 10 mol % of units derived from ethylene;
• wherein each inter-polymer independently has:
• i) a diad distribution of propylene in the inter-polymer showing a ratio of experimentally determined diad distribution over the calculated Bemoullian diad distribution of less than 1.07;
• ii) a storage modulus G′, determined upon cooling, intersecting a value of 0.3 M Pa at a temperature of less than 85° C. measured at a frequency of 1 Hz;
• iii) a G″/G′ ratio of 18 or more when G′ is 10 Pa;
• and
• iv) a viscosity of 5000 mPa·sec or less at 190° C., and
• combining the inter-polymers into a blend and
• atomizing, spiral spraying, oscillation spraying or melt blowing the blend onto a substrate.

A process for atomizing, spiral spraying, oscillation spraying or melt blowing propylene copolymers onto a substrate comprising selecting a poly-alpha olefin inter-polymer comprising:

• A) from 60 to 94% of units derived propylene and
• B) from 6 to 40 mol % of units derived from one or more of butene, hexene and octene;
• wherein the inter-polymer has:
• i) a diad distribution of propylene in the inter-polymer showing a ratio of experimentally determined diad distribution over the calculated Bernoullian diad distribution of less than 1.07;
• ii) a storage modulus G′, determined upon cooling, intersecting a value of 0.3 M Pa at a temperature of less than 85° C. measured at a frequency of 1 Hz;
• iii) a G″/G′ ratio of 18 or more when G′ is 10 Pa;
• and
• iv) a viscosity of 5000 mPa·sec or less at 190° C., and
• atomizing, spiral spraying, oscillation spraying or melt blowing the inter-polymer onto a substrate.

A process for atomizing, spiral spraying, oscillation spraying or melt blowing a blend of copolymers onto a substrate comprising selecting two or more different poly-alpha olefin inter-polymers wherein each inter-polymer independently comprises:

• A) from 60 to 94 mol % of units derived from an alpha mono-olefin having from 3 to 6 carbon atoms and
• B) from 6 to 40 mol % of units derived from ethylene or one or more other mono-olefins having from 4 to 10 carbon atoms and at least one carbon atom more than A);
• and
• C) optionally from 0 to 10 mol % of units derived from another copolymerizable unsaturated hydrocarbon, different from A) and B);
• wherein each inter-polymer has:
• i) an Mw/Mn of 6 or less;
• ii) a storage modulus G′, determined upon cooling, intersecting a value of 0.3 M Pa at a temperature of less than 85° C. measured at a frequency of 1 Hz;
• iii) a G″/G′ ratio of 18 or more when G′ is 10 Pa;
• and
• iv) a viscosity of 5000 mPa·sec or less at 190° C., and
• combining the inter-polymers into a blend, and
• atomizing, spiral spraying, oscillation spraying or melt blowing the blend onto a substrate.

A process for spraying propylene copolymers comprising selecting a hot melt adhesive composition comprising a copolymer comprising propylene and up to 50 mole % comonomer, said copolymer having

• an Mw of between 20,000 to 100,000;
• an Mw/Mn of 4 or less:,
• a G″/G′ of 18 or more, when G′ is 10 Pa;
• a Tg of about −5° C. or less;
• a Tm of about 90° C. or less;
• an amorphous content of at least 50%,
• a crystallinity of less than 15%,
• a heat of fusion of at least 5 J/g
• a viscosity of 5000 mPa·sec or less at 190° C.;
• and
• a melting range of less than 75° C., and
• atomizing, spiral spraying, oscillation spraying or melt blowing the hot melt adhesive selected onto a substrate.