Flame Retardancy and Mechanical Pro

Flame Retardancy and Mechanical Properties of Kenaf Filled Polypropylene (PP)

Containing Ammonium Polyphosphate (APP)

(Kerencatan Nyalaan dan Sifat Mekanik Kenaf Berpengisi Polipropilena

yang Mengandungi Ammonia Polifosfat (APP))

Atikah Ismail, Azman Hassan*, Aznizam Abu Bakar & M. Jawaid

Abstract

The effects of ammonium polyphosphate (APP) as flame retardant and kenaf as fillers on flammability, thermal and

mechanical properties of polypropylene (PP) composites were determined. Test specimens were prepared by using a co-
rotating twin screw extruder for the compounding process followed by injection molding. The flame retardancy of the

composites was determined by using limiting oxygen index (LOI) test. Addition of flame retardant into kenaf-PP composites

significantly increased the LOI values that indicated the improvement of flame retardancy. Thermogravimetric analysis

was done to examine the thermal stability of the composites. The addition of kenaf fiber in PP composites decreased

the thermal stability significantly but the influence of APP on thermal properties of the kenaf-filled PP composites was

not significant. The flexural strength and modulus of the composites increased with the addition of APP into kenaf filled

PP composite. The addition of APP into kenaf filled PP causes increase in the impact strength while increasing the APP

content in the kenaf filled PP composite show decrease in impact strength.

Keywords: Flame retardancy; mechanical properties; natural fiber polymer composites

Kesan ammonia polifosfat (APP) sebagai rencatan nyalaan dan kenaf sebagai pengisi ke atas sifat-sifat kebolehupayaan

nyalaan, terma dan mekanik bagi komposit polipropilena (PP) telah dikaji. Spesimen ujian telah disediakan dengan

menggunakan alat penyemprit skru berkembar untuk proses penyebatian dan diikuti dengan alat acuan suntikan.

Kerencatan nyalaan bagi komposit juga telah ditentukan dengan menggunakan alat ujian pengehad indeks oksigen (LOI).

Penambahan perencat kebakaran ke dalam komposit kenaf-PP meningkatkan nilai LOI yang menunjukkan kemajuan dalam

keupayaan rencatan nyalaan. Analisis termogravimetri dilakukan untuk memeriksa kestabilan terma bagi komposit.

Penambahan serat kenaf ke dalam komposit PP menurunkan kestabilan terma secara ketara tetapi sebaliknya, kesan APP ke

atas sifat-sifat terma bagi kenaf berpengisi komposit PP tidak mempunyai perubahan yang ketara. Kekuatan dan modulus

lenturan bagi komposit meningkat dengan penambahan APP ke dalam kenaf yang berpengisi komposit PP. Penambahan

APP ke dalam kenaf berpengisi PP juga menyebabkan peningkatan dalam kekuatan hentaman manakala peningkatan

kandungan APP di dalam kenaf berpengisi komposit PP menunjukkan penurunan di dalam kekuatan hentaman.

Kata kunci: Rencatan nyalaan; serat semula jadi komposit polimer; sifat-sifat mekanikal

Abstrak

Introduction

Recently, the acceptance of natural fiber as fillers in the

plastic industry has been growing extensively because of

their high specific properties, biodegradability, low cost

and environment friendly. The increasing utilization of

natural fiber composites in various applications such as

automotive components and aerospace industry is due to

economic advantage as compared with other conventional

filler or fiber. Kenaf also known as Hibiscus cannabinus is

a fast growing annual growth plant cultivated for its fiber

has been investigated as filler in thermoplastic composites

(Rowell et al. 1999).

Represents as a large fraction of world polymer usage,

polypropylene (PP) has been widely used in thermoplastic

industry due to its low cost and ease processing. Higher

stiffness at lower density and resistance to a higher

temperature when not subjected to mechanical stress are

the key properties for PP. Previous study has reported

that the addition of fiber reinforcement can enhance

the modulus and strength of PP (Sameni et al. 2003).

The use of reinforced polypropylene in electrical and

automotive engineering has increased due to its excellent

high modulus which enables it to replace conventional

materials in demanding engineering applications. There

are drawbacks in PP, when natural fiber was added in PP

due to poor compatibility between fiber and PP chances of

agglomeration while processing (Nabi Saheb & Jog 1999).

Compatibilizing agent required to be added into composite

to increase the interfacial bond between PP and natural

fiber. It is due to PP which consists of hydrophobic matrix

has less tendency to form interfacial bond with hydrophilic

properties of kenaf (Srebrenkoska et al. 2009). The

430

addition of compatibilizing agent can accommodate polar

interaction such as acid-based interaction and becomes a

bridge to the hydroxyl groups on a natural fiber.

Nowadays, the demand of flame retardant materials

is increasing. PP burns rapidly with a relatively smoke-
free flame and without leaving a char residue due to its

wholly aliphatic hydroc

Kết quả (Việt) 1:

Ngọn lửa Retardancy và cơ tính của Kenaf đầy Polypropylene (PP)Có chứa amoni Polyphosphate (APP)(Kerencatan Nyalaan dan Sifat Mekanik đay Berpengisi PolipropilenaYang Mengandungi amoniac Polifosfat (ứng dụng))Atikah Ismail, Azman Hassan *, Aznizam Abu Bakar & M. JawaidTóm tắtNhững ảnh hưởng của amoni polyphosphate (APP) như ngọn lửa retardant và kenaf như chất độn cho ngăn cháy, nhiệt vàCác tính chất cơ học của vật liệu composite polypropylene (PP) được xác định. Bài kiểm tra mẫu vật đã được chuẩn bị bằng cách sử dụng một co-Luân phiên các đôi vít đùn cho quá trình kép theo ép. Retardancy lửa của cácvật liệu composite đã được xác định bằng cách sử dụng giới hạn oxy index (LOI) thử nghiệm. Bổ sung các cháy vào đay-PP compositestăng đáng kể giá trị lợi chỉ ra các cải tiến của ngọn lửa retardancy. Thermogravimetric phân tíchđã được thực hiện để kiểm tra sự ổn định nhiệt của các vật liệu tổng hợp. Việc bổ sung các sợi đay ở PP composites giảmsự ổn định nhiệt đáng kể nhưng ảnh hưởng của các ứng dụng trên các tính chất nhiệt của vật liệu composite PP đầy đay làkhông đáng kể. Flexural sức mạnh và các mô đun của các vật liệu tổng hợp gia tăng với việc bổ sung các APP vào đay đầyPP composite. Việc bổ sung các APP vào đay đầy PP nguyên nhân tăng sức mạnh tác động trong khi tăng các ứng dụngnội dung trong kenaf đầy PP composite Hiển thị giảm tác động mạnh.Từ khóa: Flame retardancy; tính chất cơ học; chất xơ tự nhiên vật liệu tổng hợp polymerKesan amoniac polifosfat (APP) sebagai rencatan nyalaan dan đay sebagai pengisi ke atas sifat-sifat kebolehupayaannyalaan, terma dan mekanik bagi komposit polipropilena (PP) telah dikaji. Spesimen ujian telah disediakan denganmenggunakan alat penyemprit skru berkembar untuk proses penyebatian dan diikuti dengan alat acuan suntikan.Kerencatan nyalaan bagi komposit juga telah ditentukan dengan menggunakan alat ujian pengehad indeks oksigen (LOI).Penambahan perencat kebakaran ke komposit dalam đay-PP nilai meningkatkan LOI yang kemajuan menunjukkan dalamkeupayaan rencatan nyalaan. Analisis termogravimetri dilakukan untuk memeriksa kestabilan terma bagi komposit.Penambahan serat kenaf ke dalam komposit PP menurunkan kestabilan terma secara ketara tetapi sebaliknya, kesan APP keATAS sifat-sifat terma bagi đay berpengisi komposit PP tidak mempunyai perubahan yang ketara. Kekuatan dan mô đunlenturan bagi komposit meningkat dengan penambahan APP ke dalam kenaf yang berpengisi komposit trang PenambahanAPP ke dalam đay berpengisi PP juga menyebabkan peningkatan dalam kekuatan hentaman manakala peningkatankandungan APP di dalam đay berpengisi komposit PP menunjukkan penurunan di dalam kekuatan hentaman.Kata kunci: Rencatan nyalaan; serat semula jadi komposit polimer; sifat-sifat mekanikalAbstrakGiới thiệuRecently, the acceptance of natural fiber as fillers in theplastic industry has been growing extensively because oftheir high specific properties, biodegradability, low costand environment friendly. The increasing utilization ofnatural fiber composites in various applications such asautomotive components and aerospace industry is due toeconomic advantage as compared with other conventionalfiller or fiber. Kenaf also known as Hibiscus cannabinus isa fast growing annual growth plant cultivated for its fiberhas been investigated as filler in thermoplastic composites(Rowell et al. 1999).Represents as a large fraction of world polymer usage,polypropylene (PP) has been widely used in thermoplasticindustry due to its low cost and ease processing. Higherstiffness at lower density and resistance to a highertemperature when not subjected to mechanical stress arethe key properties for PP. Previous study has reportedthat the addition of fiber reinforcement can enhancethe modulus and strength of PP (Sameni et al. 2003).The use of reinforced polypropylene in electrical andautomotive engineering has increased due to its excellenthigh modulus which enables it to replace conventionalmaterials in demanding engineering applications. Thereare drawbacks in PP, when natural fiber was added in PPdue to poor compatibility between fiber and PP chances ofagglomeration while processing (Nabi Saheb & Jog 1999).Compatibilizing agent required to be added into compositeto increase the interfacial bond between PP and naturalfiber. It is due to PP which consists of hydrophobic matrixhas less tendency to form interfacial bond with hydrophilicproperties of kenaf (Srebrenkoska et al. 2009). The430addition of compatibilizing agent can accommodate polarinteraction such as acid-based interaction and becomes abridge to the hydroxyl groups on a natural fiber.Nowadays, the demand of flame retardant materialsis increasing. PP burns rapidly with a relatively smoke-free flame and without leaving a char residue due to itswholly aliphatic hydroc