Blends of poly(etherketoneketone) polymers
The present invention relates to blends of poly(ether ketone ketone) (PEKK) polymers, in particular to certain blends endowed with lower melting point than traditional PEKK polymers, yet maintaining high crystallinity and rapid crystallization behaviour, which are composed of a major amount of a first nucleophilic PEKK having a first T/I ratio, and a minor amount of a second PEKK having a second T/I ratio higher than the first T/I ratio; to methods of making the same, and to uses thereof in various fields.
1 . A composition [composition (C)] comprising:
a major amount of a first PEKK polymer [polymer (PEKK low )] comprising recurring units (R T ) and recurring units (R I ), having a first molar content of units (R T ) [(T low )] and a first molar content of units (R I ) [(I low )], with
T
low
(
mol
.
%
)
=
[
units
(
R
T
)
]
low
[
units
(
R
T
)
]
low
+
[
units
(
R
I
)
]
low
×
100
and with
I
low
(
mol
.
%
)
=
[
units
(
R
I
)
]
low
[
units
(
R
T
)
]
low
+
[
units
(
R
I
)
]
low
×
100
,
so defining a first T/I ratio [(T/I) low ], with
(
T
/
I
)
low
=
T
low
I
low
;
wherein recurring unit (R T ) is represented by formula (T):
and recurring unit (R I ) is represented by formula (I):
wherein:
each R 1 and R 2 , at each instance, is independently selected from the group consisting of an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, and a quaternary ammonium; and
each i and j, at each instance, is an independently selected integers ranging from 0 to 4; and
a minor amount of a second PEKK polymer [polymer (PEKK high )] comprising said recurring units (R I ) and said recurring units (R T ), having a second molar content of units (R T ) [(T high )] and a second molar content of units (R I ) [(I high )], with
T
high
(
mol
.
%
)
=
[
units
(
R
T
)
]
high
[
units
(
R
T
)
]
high
+
[
units
(
R
I
)
]
high
×
100
and with
I
high
(
mol
.
%
)
=
[
units
(
R
I
)
]
high
[
units
(
R
T
)
]
high
+
[
units
(
R
I
)
]
high
×
100
,
so defining a second T/I ratio [(T/I) high ], with
(
T
/
I
)
high
=
T
high
I
high
;
wherein polymer (PEKK low ) is a nucleophilic PEKK; and
wherein the (T/I) low of PEKK low is lower than the (T/I) high of PEKK high ; and
wherein the following inequality is satisfied:
T high −T low ≤17 mol. %.
2 . The composition (C) according to claim 1 , wherein said composition possesses:
a melting temperature (T m ) of less than or equal to 330° C.;
a heat of fusion (ΔH f ) exceeding 25 J/g;
no crystallization peak upon heating, on second DSC heat scan “cold crystallization peak”; and
a relation between melting temperature T m in ° C. determined on second DSC heat scan and crystallization temperature (T c in ° C.) determined on first DSC cooling scan, satisfying the following inequality:
T c ≥1.3716× T m −190° C.,
wherein T m , T c , ΔH f and the absence of cold crystallization peak are measured by differential scanning calorimetry (DSC) according to ASTM D3418-03, E1356-03, E793-06, E794-06 standard, applying the following conditions:
first DSC heat scan: 30.00° C. to 400.00° C. at 20.00° C./min, isothermal at 400.00° C. for 1 min;
first DSC cooling scan: 400.00° C. to 30.00° C. at 20.00° C./min, isothermal for 1 min;
second DSC heat scan: 30.00° C. to 400.00° C. at 20.00° C./min, isothermal at 400.00° C. for 1 min.
3 . The composition (C) according to claim 1 , wherein the recurring units (R T ) and (R I ) are respectively represented by formulas (T′) and (I′):
and
4 . The composition (C) according to claim 1 , wherein the polymer (PEKK low ) and the polymer (PEKK high ) are collectively referred as the polymers (PEKK), and wherein:
said polymers (PEKK) comprise recurring units (R T ) and recurring units (R I ), in a combined amount of at least 60 mol. % of the recurring units in the polymers (PEKK) are recurring units (R T ) and (R I ), the mol. % being based on the total number of moles in the polymers (PEKK); and/or
polymers (PEKK) may comprise minor amounts of recurring units different from recurring units (R T ) and recurring units (R I ), which are selected from the group consisting of formulae (J-A) to (J-O), herein below:
wherein:
each of R′, equal to or different from each other, is selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium;
j′ is zero or is an integer from 0 to 4.
5 . The composition (C) according to claim 1 , wherein:
the polymer (PEKK low ) comprises fluorine, in amounts of exceeding 100 ppm, and/or comprising Al in an amount of below 50 ppm, whereas Al and F content are determined by elemental analysis, such as ICP-OES analysis for Al and Combustion-ion chromatography for fluorine; and/or
the polymer (PEKK low ) has a thermal decomposition temperature at 1 wt. % T d (1%) of at least 500° C., as measured by thermal gravimetric analysis according to ASTM D3850, heating from 30° C. to 800° C. under nitrogen using a heating rate of 10° C./min.
6 . The composition (C) according to claim 1 , wherein:
the polymer (PEKK low ) has a (T/I) low of at least 50/50, and/or a (T/I) low of at most 64/36; and/or
the polymer (PEKK high ) has a (T/I) high of at least 65/35; and/or a (T/I) high of at most 75/25; and/or
polymer (PEKK low ) and polymer (PEKK high ) are such that 16 mol %≥T high −T low ≥3 mol %.
7 . The composition (C) according to claim 1 , wherein the polymer (PEKK high ) is a nucleophilic PEKK, and possesses a fluorine content of exceeding 100 ppm, and/or an Al content of below 50 ppm, whereas Al and F content are determined by elemental analysis, such as ICP-OES analysis for Al and Combustion-ion chromatography for fluorine.
8 . The composition (C) according to claim 1 , wherein the weight ratio between polymer (PEKK low ) and polymer (PEKK high ) is of at least 60/40, and/or it is of at most 99/1.
9 . The composition (C) according to claim 1 , wherein:
the composition further comprises of at least one nitride (NI) of an element having an electronegativity (ε) of from 1.3 to 2.5; and/or
the composition further comprises one or more than one additional ingredients different from nitride (NI), and selected from the group consisting of colorants, pigments, light stabilizers, heat stabilizers, antioxidants, acid scavengers, processing aids, nucleating agents, internal lubricants and/or external lubricants, flame retardants, smoke-suppressing agents, anti-static agents, anti-blocking agents, heat, electric and magnetic conductive materials, reinforcing fibrous additives and reinforcing non-fibrous additives.
10 . The composition according to claim 1 , wherein the total weight of polymer (PEKK low ) and polymer (PEKK high ), based on the total weight of the inventive composition (C), is equal to or above 60 wt. %; and/or
wherein composition (C) does not comprise any other polyaryletherketone polymer [polymer (PAEK)] beside polymer (PEKK low ) and polymer (PEKK high ), whereas polymer (PAEK) is a polymer comprising recurring units, more than 50% moles of said recurring units are recurring units (R* PAEK ) comprising a Ar*—C(O)—Ar*′ group, with Ar* and Ar*′, equal to or different from each other, being aromatic groups, which is not polymer (PEKK low ) or polymer (PEKK high ); and/or
wherein composition (C) essentially consists of polymer (PEKK low ) and polymer (PEKK high ); or
wherein, when used, the total weight of a nitride (NI) in the composition (C) is of at least about 0.1 wt. %, and/or of at most about 10 wt. %, based on the total weight of the composition (C).
11 . A method of making the composition (C) according to claim 1 , wherein said method comprises admixing polymer (PEKK low ), polymer (PEKK high ), optionally with other constituents; wherein said admixing may be achieved by dry or powder blending, suspension or slurry mixing, solution mixing, melt mixing or any combination thereof.
12 . A shaped article comprising the composition (C) according to claim 1 .
13 . A method of making the shaped article of claim 12 , said method comprising processing composition (C) by at least one of injection molding, extrusion, compression molding, additive manufacturing, coating, continuous fiber impregnation, and continuous fiber composite lamination/consolidation or combinations thereof.
14 . A method of making a composite, said method comprising impregnating reinforcing fibers with a matrix of composition (C) according to claim 1 .
15 . A method of making an assembly comprising a first substrate layer and a second substrate layer, said method comprising positioning a tie-layer made from the composition (C) according to claim 1 between and in contact with the said first substrate and the said second substrate.