Process for preparing polypropylene compounds for metallization and metallization thereof

Abstract

A method of preparing a polypropylene compound substrate for metallization is disclosed, the method comprising treating a surface of the substrate with a pre-etch treatment fluid comprising toluene. The treated surface may thus be more suitable for etching compared to conventional processes. Also disclosed is a metallized article comprising a polypropylene compound substrate 5 and a metal layer attached to the substrate wherein the peel strength of the attachment of the metal layer to the substrate is > = 0.10 N / mm.

Description

Technical Field

[0001] This invention generally relates to compounds comprising primarily propylene (polypropylene blends). More particularly, this invention relates to the preparation of polypropylene blends for metallization and the metallization of such compounds. Background Technology

[0002] In recent years, manufacturers have increased the use of metallized plastic components in a variety of products. For example, metallized polymer components are used in electrical and electronic (E&E) equipment, automotive equipment, computer mainframes, office equipment, machinery, and packaging. Typically, metal deposition on plastic surfaces is achieved through techniques such as electroless plating and electroplating. A key challenge in electroless plating of polymer surfaces is achieving a strong and durable bond between the metal and the polymer, as they possess properties that make them inherently incompatible; for example, they have different surface energies and coefficients of thermal expansion (CTE). Generally, to facilitate strong adhesion between the metal and polymer surfaces, chemical and / or surface morphology modifications to the polymer substrate surface are necessary.

[0003] Conventional methods for modifying polymeric substrates involve etching the polymer surface with a strong oxidizing solution (e.g., hexachromic acid or acidified potassium permanganate) prior to electroless plating. This etching step achieves (i) the formation of nanopores / micropores that allow for the anchoring / nucleation and / or mechanical interlocking of metal particles and / or (ii) the generation of polar groups, such as hydroxyl, carbonyl, and carboxyl groups, on the polymer surface. For certain thermoplastic polymers (e.g., acrylonitrile-butadiene-styrene copolymer (ABS)), the efficiency of this etching step has been widely demonstrated. In the ABS matrix, butadiene (BD) domains are uniformly dispersed in styrene-acrylonitrile (SAN), where the double bonds of BD are selectively etched by the oxidizing agent, thereby forming microcavities and polar groups. On the other hand, in the case of hydrophobic thermoplastic polymers (e.g., polypropylene (PP)), the above etching step is generally ineffective. Summary of the Invention

[0004] It is necessary to make polypropylene blends suitable for metallization using standard chemical plating and electroplating processes. The method of this invention treats the polypropylene blend substrate with toluene to make it more suitable for etching. This pre-etching treatment targets certain components of the polypropylene blend substrate to create nanopores / micropores. After creating these nanopores / micropores through the pre-etching treatment, the polypropylene blend substrate is etched with a typical etching material. The sequential treatment and etching of the polypropylene blend surface creates nanopores / micropores that facilitate metal anchoring during the metallization process, thereby increasing the adhesive strength between the two surfaces compared to conventional processes.

[0005] Some configurations of this disclosure include a method comprising forming a polypropylene compound substrate and treating the substrate surface with a pre-etching fluid containing toluene for a period of time ranging from 5 to 300 seconds, wherein the pre-etching fluid is at a temperature ranging from 25°C to 95°C during this period.

[0006] Some configurations of this disclosure include a metallized article comprising a polypropylene compound substrate and a metal layer attached to the substrate, wherein the peel strength of the metal layer to the substrate is >0.10 N / mm.

[0007] The following includes definitions of all terms and phrases used throughout this specification.

[0008] The term “about” or “approximately” is defined as close to, as understood by those skilled in the art. In one non-limiting embodiment, the term is defined as within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

[0009] For the purposes of this invention, “X, Y and / or Z” can be interpreted as only X, only Y, only Z, or any combination of two or more of X, Y and Z (e.g., XYZ, XY, XZ, YZ).

[0010] The terms “wt%”, “vol%”, or “mol%” refer to the weight, volume, or mole percentage of a component, based on the total weight, volume, or number of moles of the material containing that component. In a non-limiting example, 10 moles of a component in 100 moles of material constitutes 10 mol% of the component.

[0011] The term “substantially” and its variations are defined as including the range of 10%, 5%, 1%, or 0.5%.

[0012] The terms “suppress” or “reduce” or “prevent” or “avoid” or any variations thereof, when used in the claims and / or description, include any measurable reduction or complete suppression to achieve the desired result.

[0013] The term “effective”, as used in the specification and / or claims, means sufficient to achieve the desired, anticipated, or intended result.

[0014] When used in conjunction with the terms “comprising,” “including,” “containing,” or “having,” the use of the word “a” or “a kind” can mean “one / kind,” but can also be consistent with “one / kind or more / kinds,” “at least one / kind,” and “one / kind or more than one / kind.”

[0015] The words “contains,” “has,” “includes,” or “contains” are inclusive or open-ended and do not exclude additional undocumented elements or methodological steps.

[0016] The process of this invention may include, constitute, consist of, or be composed of specific ingredients, components, compositions, compounds, etc., disclosed throughout the specification as “comprising,” “substantially constitute,” or “compose of.”

[0017] The term "primarily," as used in the specification and / or claims, means greater than any one of 50 wt%, 50 mol%, and 50 vol%. For example, "primarily" can include all values ​​and ranges from 50.1 wt% to 100 wt%, 50.1 mol% to 100 mol%, or 50.1 vol% to 100 vol%.

[0018] Other objects, features, and advantages of the present invention will become apparent from the following drawings, detailed descriptions, and embodiments. However, it should be understood that while the drawings, detailed descriptions, and embodiments illustrate specific embodiments of this disclosure, they are given by way of example only and are not intended to be limiting. Furthermore, variations and modifications are expected to become apparent to those skilled in the art from these detailed descriptions within the spirit and scope of the invention. In further embodiments, features from a specific embodiment may be combined with features from other embodiments. For example, a feature from one embodiment may be combined with features from any other embodiment. In further embodiments, additional features may be added to the specific embodiments described herein. Attached Figure Description

[0019] For a more complete understanding, please now refer to the following description in conjunction with the accompanying drawings, wherein:

[0020] Figure 1 A conceptual flowchart illustrating an example of the present invention for preparing polypropylene blends for metallization and methods for metallizing these compounds.

[0021] Figure 2 Scanning electron microscopy (SEM) images of specific polypropylene blends treated with hexachromic sulfuric acid (HCSA) at 70°C for 20 minutes are depicted.

[0022] Figure 3 SEM images of a specific polypropylene blend subjected to a sequential pretreatment with toluene at approximately 85°C for 30 seconds followed by HCSA treatment at 70°C for 20 minutes were depicted.

[0023] Figure 4 It is a graph depicting the peel strength of copper plated on ABS and polypropylene blends with different pretreatments. Detailed Implementation

[0024] In embodiments of this disclosure, the articles based on the polypropylene blend are treated with toluene prior to etching with, for example, hexachromic sulfuric acid (HCSA), trichromium, potassium permanganate, and manganese-based etching solutions, or combinations thereof. In some configurations, the polypropylene blend incorporates polycarbonate and / or styrene-acrylonitrile-grafted butadiene to help increase the surface polarity of the polypropylene blend, thereby making the surface of the polypropylene blend more suitable for the etching process.

[0025] In aspects of this disclosure, the polypropylene composition comprises 55 wt% to 95 wt% or any range thereof, including 55 wt% to 60 wt%, 60 wt% to 65 wt%, 65 wt% to 70 wt%, 70 wt% to 75 wt%, 75 wt% to 80 wt%, 80 wt% to 85 wt%, 85 wt% to 90 wt%, and 90 wt% to 95 wt% of polypropylene.

[0026] In some embodiments of this disclosure, polypropylene is melt-blended with reinforcing fillers and additives in an extruder setup. In some configurations, the reinforcing fillers include one or more of the following: inorganic materials, talc, silica, glass beads, hollow glass beads, glass fibers, and alumina fibers. In aspects of this disclosure, the polypropylene compound comprises 5 wt% to 40 wt% or any range thereof, including 5 wt% to 10 wt%, 10 wt% to 15 wt%, 15 wt% to 20 wt%, 20 wt% to 25 wt%, 25 wt% to 30 wt%, 30 wt% to 35 wt%, and 35 wt% to 40 wt% of reinforcing fillers.

[0027] In some embodiments, the polypropylene compound comprises additives, such as one or more of the following: polycarbonate and / or styrene-acrylonitrile-grafted butadiene. The amount of these additives in the polypropylene compound can be optimized to produce a polypropylene compound capable of achieving high metal adhesion and exhibiting mechanical, thermal, and electrical properties suitable for the target application. In some aspects, the polypropylene compound comprises 2 wt% to 20 wt% or any range thereof, including 2 wt% to 4 wt%, 4 wt% to 6 wt%, 6 wt% to 8 wt%, 8 wt% to 10 wt%, 10 wt% to 12 wt%, 12 wt% to 14 wt%, 14 wt% to 16 wt%, 16 wt% to 18 wt%, and 18 wt% to 20 wt% of polycarbonate. Furthermore, in some aspects, the polypropylene blend comprises 2 wt% to 20 wt% or any range thereof, including 2 wt% to 4 wt%, 4 wt% to 6 wt%, 6 wt% to 8 wt%, 8 wt% to 10 wt%, 10 wt% to 12 wt%, 12 wt% to 14 wt%, 14 wt% to 16 wt%, 16 wt% to 18 wt%, and 18 wt% to 20 wt% of styrene-acrylonitrile-grafted butadiene. Although this disclosure is not limited to the following theory, it is believed that incorporating polycarbonate and / or styrene-acrylonitrile-grafted butadiene into polypropylene contributes to increased surface polarity due to the preferential migration of these additives to the surface. In some embodiments, the polypropylene blend further comprises one or more of the following: stabilizers, coupling agents, and dispersants.

[0028] The polypropylene blends disclosed herein can be prepared by various methods known in the art. For example, components (such as polypropylene, reinforcing fillers, and additives) can be mixed together and then melt-blended to form a polypropylene blend. The melt blending of the components may include the use of shear force, tensile force, compressive force, ultrasonic energy, electromagnetic energy, thermal energy, or a combination of at least one of the above-mentioned forms of force or energy.

[0029] In some aspects, one or any of the aforementioned components described herein may first be blended with each other, for example, dry-blending, such as by manual mixing or in a high-speed mixer. The blend may then be fed via a hopper into the throat of a twin-screw extruder. In some aspects, at least one component may be introduced by feeding it directly into the extruder through a side filler at the throat and / or downstream, or by compounding it with polypropylene into a masterbatch and feeding it into the extruder. The extruder used in this disclosure may have a single screw, multiple screws, meshing co-rotating or counter-rotating screws, non-meshing co-rotating or counter-rotating screws, reciprocating screws, screws with pins, screws with screens, barrels with pins, rollers, punches, helical rotors, co-kneaders, disc assembly machines, various other types of extrusion equipment, or combinations including at least one of the foregoing. Extruders can generally be operated at temperatures above those required to melt and flow the composition. In some aspects, the temperature of the melt in the extruder barrel may be kept as low as possible to avoid excessive thermal degradation of the components. The molten compound exits the extruder through a small outlet orifice in the die. The extrudate can be quenched and granulated in a water bath. The resulting granules can be of any desired length (e.g., a quarter inch or shorter). These granules can then be used for subsequent molding, shaping, or forming.

[0030] If desired, a mixture containing any combination of the aforementioned components can undergo multiple blending and molding steps. For example, a plastic polypropylene compound can first be extruded and formed into granules. The granules can then be fed into a molding machine, where they can be shaped into any desired shape or product. In some aspects, plastic polypropylene compounds from a single melt mixer can be formed into sheets or strips and subjected to post-extrusion treatments such as annealing, uniaxial orientation, or biaxial orientation.

[0031] It also provides shaped, molded, cast, or molded articles containing plastic polypropylene blends. Plastic polypropylene blends can be molded into useful shaped articles by a variety of methods, such as injection molding, extrusion, rotational molding, blow molding, 3D printing, additive manufacturing, and thermoforming. Articles can be molded articles, thermoformed articles, extruded films, extruded sheets, cellular structures, one or more layers of multilayer articles, substrates for coated articles, and substrates for metallized articles (e.g., articles containing plastic polypropylene blends coated with a metal layer).

[0032] refer to Figure 1 This disclosure includes a method 10 for metallizing polypropylene blends. For example... Figure 1As shown, method 10 includes, at frame 100, melt-blending multiple components comprising polypropylene, reinforcing fillers, and additives to form a matrix. The melt blending can be performed in an extruder or a melt mixer. In some configurations, the additives may include one or more of the following components: polycarbonate and styrene-butadiene-styrene. And in some configurations, the reinforcing fillers may include one or more of the following: glass beads, glass fibers, and other ceramic fibers.

[0033] In the example shown, box 101 includes treating the substrate surface with a pre-etching fluid containing toluene. In some configurations, a surface treatment is performed at frame 101 such that the temperature of the pre-etching fluid is in any range from 25°C to 95°C or between, including 25°C to 30°C, 30°C to 35°C, 35°C to 40°C, 40°C to 45°C, 45°C to 50°C, 50°C to 55°C, 55°C to 60°C, 60°C to 65°C, 65°C to 70°C, 70°C to 75°C, 75°C to 80°C, 80°C to 85°C, 85°C to 90°C, and 90°C to 95°C for 5 to 300 seconds or between, including 5 to 30 seconds, 30 to 60 seconds, 60 to 90 seconds, 90 to 120 seconds, 120 to 150 seconds, 150 to 180 seconds, 180 to 210 seconds, 210 to 240 seconds, 240 to 270 seconds, and 270 to 300 seconds. In this disclosure, the substrate may initially be at a lower temperature than the pre-etching fluid, for example, at room temperature (20°C to 22°C); and once the substrate comes into contact with the pre-etching fluid, the surface of the substrate is expected to reach thermal equilibrium with the pre-etching fluid, depending on how long the pre-etching fluid is in contact with the substrate.

[0034] As shown in the example, method 10 includes etching the substrate surface at block 102 with any one of hexachromic sulfuric acid (HCSA), trichromium, potassium permanganate, and manganese-based etching solutions or combinations thereof. In some configurations, etching is performed on the surface at frame 102 such that the temperature of the etching solution is in any range between 25°C and 80°C, including 25°C to 30°C, 30°C to 35°C, 35°C to 40°C, 40°C to 45°C, 45°C to 50°C, 50°C to 55°C, 55°C to 60°C, 60°C to 65°C, 65°C to 70°C, 70°C to 75°C, and 75°C to 80°C for 5 to 60 minutes and any range therebetween, including 5 to 10 minutes, 10 to 15 minutes, 15 to 20 minutes, 20 to 25 minutes, 25 to 30 minutes, 30 to 35 minutes, 35 to 40 minutes, 40 to 45 minutes, 45 to 50 minutes, 50 to 55 minutes, and 55 to 60 minutes. In this disclosure, the substrate may initially be at a lower temperature than the etching solution, for example, at room temperature (20°C to 22°C); and once the substrate comes into contact with the etching solution, it is expected that the substrate surface can reach thermal equilibrium with the etching solution, depending on how long the etching solution is in contact with the substrate.

[0035] In the example shown, method 10 at block 103 may include depositing colloidal palladium into micropores on the substrate surface via a chemical redox reaction. In some configurations, the deposition of colloidal palladium at block 103 is performed at a temperature of 25°C to 50°C for 1 to 10 minutes. In the example shown, after each of blocks 101, 102, and 103 in method 10, the substrate may be rinsed with water before proceeding to the next step.

[0036] In the example shown, box 104 relates to attaching a metal layer to an etched surface of a substrate. In some configurations, attaching the metal layer includes a chemical plating process. And in some configurations, attaching the metal layer includes an electroplating process. The metal attached to the substrate can be any of nickel, copper, aluminum, gold, platinum, and alloys thereof.

[0037] A suitable measure of the success of the bonding between the metal layer and the polymer substrate is by measuring the peel strength, where the greater the peel strength, the better the adhesion of the metal to the polymer substrate. In some configurations, the peel strength between the attached metal layer and the etched surface of the substrate is ≥0.10 N / mm or any range therebetween, including 0.10 to 1.5 N / mm, 0.10 to 0.20 N / mm, 0.20 to 0.30 N / mm, 0.30 to 0.40 N / mm, 0.40 to 0.50 N / mm, 0.50 to 0.60 N / mm, 0.60 to 0.70 N / mm, 0.70 to 0.80 N / mm, 0.80 to 0.90 N / mm, 0.90 to 1.0 N / mm, 1.0 to 1.10 N / mm, 1.10 to 1.20 N / mm, 1.20 to 1.30 N / mm, 1.30 to 1.40 N / mm, and 1.40 to 1.50 N / mm.

[0038] The metallized polypropylene formulations disclosed herein can be used to manufacture a variety of different components, such as components for electrical or electronic equipment, components for telecommunications equipment, radio frequency (RF) filters, EMI shielding, waveguides, antenna substrates, automotive interior components, automotive exterior components, and packaging.

[0039] Although it has been referenced Figure 1 The boxes described aspects of this disclosure, but it should be understood that the operation of this disclosure is not limited to... Figure 1 The specific boxes and / or the specific order of the boxes shown. Therefore, various aspects of this disclosure may use boxes in different ways. Figure 1 The order in which they are used to provide the functionality described in this article.

[0040] As part of this disclosure, specific embodiments are included below. These embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Those skilled in the art will readily recognize that parameters can be changed or modified to produce substantially the same results.

[0041] Example

[0042] A first polypropylene (PP) compound was prepared comprising 58 wt% polypropylene, 20 wt% low dielectric constant (Dk) glass fiber (LowDkGF: Grade-ECS305-3-K-HL, purchased from CPIC / Chongqing International Composites Co., Ltd., China), 10 wt% polycarbonate (PC), 10 wt% glass bulb (GB), and 2 wt% processing aids, including 0.1 wt% antioxidant (Irganox 1010), 0.1 wt% heat stabilizer (Irgaphos-168), 1.6 wt% coupling agent (maleic anhydride-grafted polypropylene), and 0.2 wt% nucleating agent (talc). The first polypropylene compound matrix was treated with hexachromic sulfuric acid (HCSA) at 70 °C for 20 minutes. Figure 2 Scanning electron microscopy (SEM) images of a first polypropylene compound substrate, which was treated with HCSA at 70°C for 20 minutes, were depicted.

[0043] A second polypropylene compound was prepared comprising 58 wt% polypropylene, 20 wt% LowDkGF, 10 wt% polycarbonate, 10 wt% glass bulb, and 2 wt% processing aids, including 0.1 wt% antioxidant (Irganox 1010), 0.1 wt% heat stabilizer (Irgaphos-168), 1.6 wt% coupling agent (maleic anhydride-grafted polypropylene), and 0.2 wt% nucleating agent (talc). The second polypropylene compound matrix was then sequentially treated with hot toluene at 85°C (while the matrix was initially at room temperature) for 30 seconds, followed by treatment in HCSA at 70°C for 20 minutes. Figure 3 SEM images of a second polypropylene compound substrate were depicted, which was treated with hot toluene at 85°C for 30 seconds and then with HCSA at 70°C for 20 minutes.

[0044] from Figure 2 and Figure 3 It can be seen that treating the polypropylene compound substrate with hot toluene followed by HCSA treatment helps to form interlocking nanopores / micropores, which results in relatively better metal adhesion, as evidenced by higher peel strength values, such as... Figure 4 As shown.

[0045] Figure 4The results show that for the second polypropylene blend sample, a metal peel strength as high as 0.27 ± 0.05 N / mm was obtained after sequential exposure to hot toluene and HCSA. Notably, although the peel strength value obtained for the polypropylene blend substrate pretreated with HCSA or hot toluene alone was approximately 0.08 N / mm, a significantly higher peel strength value (approximately 0.27 N / mm) was evident for the polypropylene blend substrate pretreated with hot toluene and HCSA sequentially. This suggests a non-obvious synergistic effect of combining the two pretreatments (hot toluene and HCSA) to achieve the desired improvement in metal adhesion.

[0046] Furthermore, it was found that the peel strength of the adhesion between the polypropylene compound and the metal achieved due to continuous exposure to hot toluene and HCSA was similar to the peel strength value of ABS obtained using standard HCSA pretreatment. Figure 4 As shown. The results obtained appear to indicate that pretreatment with hot toluene helps to swell the surface of the polypropylene compound, thereby forming nanopores / micropores upon exposure to HCSA. It also confirms the mechanical interlocking of copper electroplating within the formed nanopores / micropores, which yields high metal bond strength.

[0047] When pure polypropylene (containing no additives such as polycarbonate and reinforcing fillers such as glass fiber and glass bubble or combinations thereof) is pretreated sequentially with hot toluene and HCSA as detailed in Table 1, no adverse effects are expected. Figure 4 The significant increase in peel strength values ​​shown in Table 1, using the cross-hatch method, details the qualitative evaluation of peel strength for ABS and various polypropylene blends subjected to different pretreatments, demonstrating the important role of additives in achieving the desired improved metal adhesion. Table 2 below further details the adhesion grades of various polypropylene blends subjected to different pretreatments.

[0048] Table 1

[0049]

[0050] Table 2

[0051]

[0052] In the context of this disclosure, at least 15 aspects are described. Aspect 1 is a method comprising forming a polypropylene compound substrate and treating a substrate surface with a pre-etching fluid containing toluene for a period ranging from 5 to 300 seconds, wherein the pre-etching fluid is at a temperature ranging from 25°C to 95°C during this period. Aspect 2 is the method of Aspect 1, wherein forming the polypropylene compound substrate comprises melt blending multiple components including polypropylene, reinforcing fillers, and additives. Aspect 3 is the method of Aspect 2, wherein melt blending is performed in an extruder and / or a melt blender. Aspect 4 is the method of any one of Aspects 1 to 3, further comprising etching the surface with any one of hexachromic sulfuric acid (HCSA), trichromium, potassium permanganate, and a manganese-based etching solution, or combinations thereof. Aspect 5 is the method of Aspect 4, further comprising depositing colloidal palladium into micropores on the surface via a chemical redox reaction. Aspect 6 is the method of Aspect 5, further comprising attaching a metal layer to the etched surface of the substrate. Aspect 7 is the method of aspect 6, wherein the peel strength of the adhesion between the metal layer and the etched surface of the substrate is ≥0.10 N / mm.

[0053] Aspect 8 is a metallized article comprising: a polypropylene compound substrate, and a metal layer attached to the substrate, wherein the peel strength of the adhesion between the metal layer and the substrate is ≥0.10 N / mm. Aspect 9 is a metallized article of aspect 8, wherein the substrate comprises polypropylene, reinforcing filler, and additives. Aspect 10 is a metallized article of aspect 9, wherein the reinforcing filler comprises one or more of the following: inorganic materials, talc, silica, glass beads, hollow glass beads, glass fibers, and alumina fibers. Aspect 11 is a metallized article of any of aspects 9 and 10, wherein the additive comprises one or more of the following: polycarbonate and styrene-acrylonitrile grafted butadiene. Aspect 12 is a metallized article of any of aspects 9 to 11, wherein the substrate comprises 5-40 wt% reinforcing filler. Aspect 13 is a metallized article of any of aspects 9 to 12, wherein the substrate comprises 2-20 wt% additives. Aspect 14 is a metallized article of any of Aspects 9 to 13, wherein the substrate further comprises one or more of the following: stabilizers, coupling agents, and dispersants. Aspect 15 is a metallized article of any of Aspects 8 to 14, wherein the metallized article is configured to be included in one or more of the following: components used in electrical or electronic equipment, components of telecommunications equipment, radio frequency (RF) filters, EMI shielding, waveguides, antenna substrates, automotive interior components, automotive exterior components, and packaging.

[0054] Although the embodiments and advantages of this application have been described in detail, it should be understood that various changes, substitutions, and modifications can be made therein without departing from the spirit and scope of the embodiments as defined by the appended claims. Furthermore, the scope of this application is not intended to be limited to the specific embodiments of the processes, machines, manufactures, compositions of matter, methods, and steps described in the specification. As will be readily understood by those skilled in the art from the foregoing disclosure, existing or later-developed processes, machines, manufactures, compositions of matter, methods, or steps that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Therefore, the appended claims are intended to include such processes, machines, manufactures, compositions of matter, methods, or steps within their scope.

Claims

1. A method, comprising: Forming a polypropylene compound substrate; as well as The substrate surface is treated with a pre-etching fluid containing toluene for a period of time ranging from 5 to 300 seconds, wherein the pre-etching fluid is at a temperature ranging from 30°C to 95°C during this period.

2. The method of claim 1, wherein forming the polypropylene compound substrate comprises: Melt blends include multiple components such as polypropylene, reinforcing fillers, and additives.

3. The method of claim 2, wherein melt blending is carried out in an extruder and / or a melt blender.

4. The method according to any one of claims 1-3, further comprising: The surface is etched using any one of hexachromic sulfuric acid (HCSA), trichromium, potassium permanganate, and manganese-based etching solutions, or combinations thereof.

5. The method according to claim 4, further comprising: Colloidal palladium is deposited into the micropores on the surface via a chemical redox reaction.

6. The method according to claim 5, further comprising: The metal layer is attached to the etched surface of the substrate.

7. The method of claim 6, wherein the peel strength of the adhesion between the metal layer and the etched surface of the substrate is ≥0.10 N / mm.

8. Metallized articles, including: Polypropylene compound substrate; and A metal layer attached to a substrate, wherein the peel strength of the metal layer to the substrate is ≥0.10 N / mm.

9. The metallized article according to claim 8, wherein the substrate comprises polypropylene, reinforcing filler, and additives.

10. The metallized article according to claim 9, wherein the reinforcing filler comprises one or more of the following: inorganic materials, talc, silica, glass beads, hollow glass beads, glass fibers, and alumina fibers.

11. The metallized article according to any one of claims 9 and 10, wherein the additive comprises one or more of the following: polycarbonate and styrene-acrylonitrile grafted butadiene.

12. The metallized article according to any one of claims 9-11, wherein the substrate comprises 5-40 wt% reinforcing filler.

13. The metallized article according to any one of claims 9-12, wherein the substrate comprises 2-20 wt% of additives.

14. The metallized article according to any one of claims 9-13, wherein the substrate further comprises one or more of the following: stabilizer, coupling agent and dispersant.

15. The metallized article according to any one of claims 8-14, wherein the metallized article is configured to be included in one or more of: components used in electrical or electronic equipment, components of telecommunications equipment, radio frequency (RF) filters, EMI shielding, waveguides, antenna substrates, automotive interior components, automotive exterior components, and packaging.

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