Polymer composition and article made from the same

1. A polymer composition comprising:

A). from 20 wt % to 30 wt % of a polycarbonate;

B). from 40 wt % to 60 wt % of a polybutylene terephthalate;

C). from 5 wt % to 30 wt % of a reinforcement fiber;

D). from 1 wt % to 10 wt % of glass bubbles, and

E). from 0.3 wt % to 2 wt % of transesterification inhibitor,

all contents are based on the total weight of the composition.

2. The composition according to claim 1 , wherein the polycarbonate is an aromatic polycarbonate derived from reaction of a diphenol of the formula (I) with a carbonic acid halide,

wherein

A is a single bond, C 1 -C 5 -alkylene, C 2 -C 5 -alkylidene, C 5 -C 6 -cycloalkylidene, —O—, —SO—, —CO—, —S—, —SO 2 —, C 6 -C 12 -arylene, onto which further aromatic rings, optionally containing heteroatoms, may be condensed, or a group of the formula (II) or (III):

B is, in each case, C 1 -C 12 -alkyl,

x in each case, independently of each other, is 0, 1 or 2,

p is 1 or 0, and

R 5 and R 6 may be selected individually for each X′, independently of each other, as hydrogen or C 1 -C 6 -alkyl,

X 1 is carbon, and

m is an integer from 4 to 7,

provided that R 5 and R 6 are both alkyl on at least one X 1 atom.

3. The composition according to claim 2 , wherein the diphenol is selected from 4,4′-dihydroxydiphe-nyl, bisphenol A, 2,4-bis(4-hydroxyphenyl)-2-methylbu-tane, 1,1-bis-(4-hydroxyphenyl)-cyclohexane, 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane, 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxydiphenyl-sulfone and their di- and tetrabrominated or chlorinated derivatives, diphenols of general formula (IVa):

in which

R 1 represents hydrogen or C 1 -C 4 -alkyl,

R 2 represents C 1 -C 4 -alkyl,

n represents 0, 1, 2 or 3, and

diphenols of general formulae (IVb), (IVc) and (IVd):

in which R 3 represents C 1 -C 4 -alkyl, aralkyl or aryl.

4. The composition according to claim 1 , wherein the polycarbonate is based on bisphenol A (2,2-bis-(4-hydroxyphenyl)-propane), or based on bisphenol A and 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (Bisphenol TMC) having the formula (IVa″):

the molar ratio of diphenol of the formula (IVa″) to bisphenol A is between 1%: 99% and 99%:1%.

5. The composition according to claim 1 , wherein the reinforcement fiber is a glass fiber, selected from the group consisting of E-glass, S-glass, AR-glass, T-glass, D-glass and R-glass.

6. The composition according to claim 1 , wherein the diameter of the glass bubble is from 1 to 50 μm.

7. The composition according to claim 1 , wherein the transesterification inhibitor is a phosphorus-containing stabilizer selected from an acidic phosphate salt, a phosphite compound, and a phosphorous oxoacid.

8. The composition according to claim 7 , wherein the acidic phosphate salt is selected from the group consisting of monozinc phosphate, sodium dihydrogen phosphate, potassium hydrogen phosphate, calcium hydrogen phosphate, sodium acid pyrophosphate and mixtures thereof,

the phosphite compound is selected those of the general formula (V):

P—(OR 1 ) 3   (V)

wherein each R 1 is the same or different and independently represents hydrogen, alkyl groups, aryl groups or any mixture thereof provided that at least one of the R′ groups is hydrogen or alkyl, and

the phosphorous oxoacid is selected from the group consisting of phosphorous acid, phosphoric acid, polyphosphoric acid, hypophosphorous acid and mixtures thereof.

9. An article, comprising:

a metal substrate; and

a plastic part made from the polymer composition according to claim 1 on the metal substrate.

10. The article according to claim 9 , wherein the metal substrate is an aluminum sheet.

11. The article according to claim 9 , which is a shell for mobile phones.

12. A process for producing an article comprising:

forming a plastic part with the polymer composition according to claim 1 on a metal substrate.

13. A process for producing an article according to claim 12 , comprising:

Step S1: treating the surface of a metal substrate to form nano-pores having a diameter of 10 nm to 30 nm on at least a part of the surface of the metal substrate; and

Step S2: injection molding the polymer composition according to claim 1 onto the treated surface of the metal substrate to form a plastic part on the metal substrate.

14. A process for producing an article comprising:

forming a plastic part on a metal substrate with a polymer composition comprising,

A). from 20 wt % to 30 wt % of a polycarbonate;

B). from 40 wt % to 60 wt % of a polybutylene terephthalate;

C). from 5 wt % to 30 wt % of a reinforcement fiber;

D). from 1 wt % to 10 wt % of glass bubbles, and

E). from 0.3 wt % to 2 wt % of transesterification inhibitor,

wherein all contents are based on the total weight of the composition, and wherein the steps of the process comprise,

Step S1: treating the surface of a metal substrate to form nano-pores having a diameter of 10 nm to 30 nm on at least a part of the surface of the metal substrate,

Step S2: injection molding the polymer composition onto the treated surface of the metal substrate to form a plastic part on the metal substrate, and

Step S3: Subjecting the article from S2 to annealing under a temperature of 50° C. to 200° C. for 1-2 hours.

15. A process for producing an article comprising:

forming a plastic part on a metal substrate with a polymer composition comprising,

A). from 20 wt % to 30 wt % of a polycarbonate;

B). from 40 wt % to 60 wt % of a polybutylene terephthalate;

C). from 5 wt % to 30 wt % of a reinforcement fiber;

D). from 1 wt % to 10 wt % of glass bubbles, and

E). from 0.3 wt % to 2 wt % of transesterification inhibitor,

wherein all contents are based on the total weight of the composition, and wherein the steps of the process comprise,

Step S1: treating the surface of a metal substrate to form nano-pores having a diameter of 10 nm to 30 nm on at least a part of the surface of the metal substrate,

Step S2: injection molding the polymer composition onto the treated surface of the metal substrate to form a plastic part on the metal substrate,

Step S3: Subjecting the article from S2 to annealing under a temperature of 50° C. to 200° C. for 1-2 hours,

Step S4: subjecting the article from S3 to anodizing.