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Abstrak :
Dilakukan penelitian pembuatan biomaterial komposit polimer-kalsium fosfat karbonat. Polimer matriks terbuat dari reaksi kering sodium chloroacetate pada suhu 192°C yang menghasilkan polyglycolide yang berpori. Larutan kalsium fosfat karbonat ditumbuhkan pada matriks polyglycolide dengan cara presipitasi. Sampel dibuat dengan berbagai macam perbandingan konsentasi PO4 3- : CO3 2- : Ca2+. Kemudian hasil presipitasi di analisa dengan difraksi sinar X untuk identifikasi fase dan pengamatan morfologi dilakukan dengan scanning electron microscopy (SEM). Hasil karakterisasi XRD menunjukkan apatit karbonat tipe A, apatit karbonat tipe B, hidroksiapatit, dan NaCl hadir dalam komposit polimer-kalsium fosfat karbonat. Hasil mikrogaf SEM menunjukkan kristal hidroksiapatit dan apatit karbonat tumbuh disamping matriks polyglicolide . Kemudian untuk mengetahui pengaruh ion Mg2+ pada pertumbuhan kristal apatit dilakukan penambahan ion Mg2+ pada sebagian sampel. Hasil yang diperoleh adalah yang mengandung fase amorf maupun fase kristal kalsium fosfat karbonat berasal dari larutan encer dengan tambahan ion CO3 2- dan Mg2+ dan hasil yang sama dapat diperoleh dari larutan yang relatif lebih kental namun hanya dengan tambahan karbonat. ......Precipitation of calcium phosphate carbonate at polymer Porous Polyglycolide have been done. Matrix polymer make from dry reaction sodium chloroacetate at 1920 C and result porous polyglycolide. Solution calcium phosphate carbonate grows at matrix polyglycolide with precipitation. Samples make with variation concentration PO4 3- : CO3 2- : Ca2+. Afterwards result from precipitation on analyze with X-ray diffraction (XRD) for fase identification and for monitoring morfology analyze with Scanning electron microscopy (SEM). Result caracteristic XRD show apatite carbonate tipe A, apatite carbonate tipe B, hydroxyapatite and NaCl be present at composite polimer calcium phosphate carbonate. Result micrograph SEM show crystal hydroxyapatite grows at matrix polyglycolide. Last for know influence ion Mg2+ at grow cristal apatite add Mg2+ at a part samples. The result sample contain fase amorf and fase crystal calsium phosphate carbonate come from liquid of solution with added ion CO3 2- and Mg2+ and the same result from thick of solution but only with added carbonate.

Abstrak :
Residual stresses are a common phenomenon in composite materials. They can either add to or significantly reduce material strength. Because of the increasing demand for high-strength, light-weight materials such as composites and their wide range of applications in the aerospace and automotive industries, in civil infrastructure and in sporting applications, it is critical that the residual stresses of composite materials are understood and measured correctly. The first part of this important book reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses. Various mathematical (analytical and numerical) methods for calculation of residual stresses in composite materials are also presented. Chapters in the first section of the book discuss the simulated hole drilling method, the slitting/crack compliance method, measuring residual stresses in homogeneous and composite glass materials using photoelastic techniques, and modeling residual stresses in composite materials. The second part of the book discusses residual stresses in polymer matrix, metal-matrix and a range of other types of composites. Moreover, the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses is discussed.

Abstrak :
Pada penelitian ini dibuat PMCs (Polymer Matrix Composites), menggunakan polipropilena (PP) sebagai matriks dan serat sorgum dan bubble glass sebagai penguat. Polipropilena dan serat sorgum memiliki sifat permukaan yang berbeda, sehingga kompatibilitas antara keduanya kurang baik. Oleh karena itu, dilakukan modifikasi permukaan serat sorgum dengan metode alkalinisasi. Proses alkalinisasi dilakukan dengan merendam serat sorgum pada larutan NaOH 2% selama 2 jam dan dilanjutkan Proses bleaching dengan menggunakan buffer dan NaClO2 selama 4 jam, serta pada penelitian akan dikomparasikan dengan bubble glass. Selanjutnya menggunakan metode hot melt mixing. Analisa pada penelitian ini adalah bagaimana pengaruh komposisi selulosa serat sorgum dan bubble glass terhadap kristalinitas dan sifat mekanik dari PP. Dari analisa DSC menunjukkan PP dengan penambahan MFC sorgum sebesar 5% wt dapat menaikkan temperatur kristalisasi sebesar 1280C dan mempercepat kristalisasi sebesar 10 detik. Dari hasil uji tarik menunjukkan dengan penambahan bubble glass sebesar 1% wt menunjukkan angka UTS tertinggi sebesar 27,59 Mpa sedangkan penambahan 0,4% wt selulosa sorgum menunjukkan angkau UTS tertinggi yaitu 27,2. ......This research conduct PMC in which Polypropylene (PP) is utilized as matrix and sorgum and glass bubbles as an reinforcement. PP and Sorghum have different surface characteristic then their coompactibilities are poor. As result, modification of sorghum by using alkalinity and bleaching is considered to bring better performance result. Akalinity is conducted initially by put sorgum immersely in NaOH solution 2% for 2 hours then bleach the solution by using buffer and NaClO2 for 4 hours. The result is then compared with glass bubbles and then using hot melt mixing method. This research brings result of how ther composition of microfibrill cellulose and glass bubbles toward their cristalinity and mechanical properties from PP. From the DSC analysis confirmed MFC sorghum PP with the addition of 5% wt can increase the crystallization temperature of 1280C and accelerate the crystallization by 10 seconds. From the tensile test results show with the addition of glass bubble at 1% wt can increase of tensile, UTS figures showed a peak of 27.59 MPa , while the addition of 0.4 wt% cellulose sorghum confirmed highest UTS is 27.2 MPa.

Abstrak :
ABSTRAK
Penelitian bertujuan untuk mengetahui pengaruh sistem pemolesan terhadap perubahan warna Nano-ionomer. Nano-ionomer dibagi menjadi empat kelompok; dipoles dengan Sof-LexTM XT, PoGOTM, OptraPol®, dan tidak dipoles. Seluruh spesimen direndam dalam larutan kopi selama tujuh hari. Perubahan warna dinilai dengan sistem CIELAB. Hasil dianalisis dengan uji One Way Anova dan Paired Samples T Test. Nilai L* mengalami penurunan yang signifikan (p < 0,05) setelah dilakukan pemolesan. OptraPol® mengalami perubahan warna terkecil. Setelah perendaman, terjadi perubahan nilai L*, a*, dan b* yang signifikan (p < 0,05) pada seluruh kelompok. OptraPol® mengalami perubahan warna terkecil namun tidak berbeda bermakna terhadap PoGOTM dan tidak dipoles.

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ABSTRACT
The aim of this study was to assess the influence of polishing systems on color change of Nano-ionomer. Specimens were divided into four groups; polished with Sof-LexTM XT, PoGOTM, OptraPol® and unpolished. Color values were evaluated using CIELAB system. Data were analyzed using One Way Anova and Paired Samples T Test. L* values were significantly lowered (p < 0,05) after polishing procedures. OptraPol® showed the least colour change. After immersion, there were significant changes in L*, a* and b* values (p < 0,05) in all groups. OptraPol® showed the littlest colour change but it was not statistically significant compared to PoGOTM and unpolished.

Abstrak :
Berbagai material aluminosilikat telah digunakan sebagai prekursor untuk geopolimer. Geopolimer mendapat kekuatannya dari polikondensasi silikat dan alumina. Metakaolin, kaolin yang kalsinasi, adalah pozzolan dengan alumina dan kemurnian silika tertinggi. Indonesia, khususnya Pulau Bangka, memiliki sejumlah besar deposit kaolin yang dijual dengan harga murah. Harga ini bisa ditingkatkan sepuluh kali ketika dijual sebagai metakaolin. Penelitian ini bertujuan untuk membandingkan sifat mekanik dan metalurgi metakaolin komersial dan kaolin Bangka yang dikalsinasi pada 700°C. Kedua metakaolin bereaksi dengan NaOH dan waterglass sebagai aktivator diikuti dengan pengawetan pada suhu kamar selama 7, 14 dan 28 hari dan suhu tinggi 60°C selama 4, 12 dan 24 jam. Sifat mekanik akan diperiksa dengan kuat tekan dan uji kuat lentur, dan uji susut sedangkan sifat metalurgi akan dievaluasi dengan SEM, dan TAM. Hasil uji mekanis akan digunakan untuk menentukan geopolimer mana yang akan berkinerja baik dengan struktur mikro dan aktivitas termal untuk mendukung temuan tersebut. Upaya-upaya ini akan dilakukan dalam rangka meningkatkan properti dari Bangka metakaolin geopolimer yang lebih unggul dari metakaolin komersial. ......Various aluminosilicate material have been used as precursor for geopolymer. Geopolymer gets its strength from the polycondensation of silicate and alumina. Metakaolin, calcinated kaolin, is pozzolan with the highest alumina and silicate purity. Indonesia, especially Bangka Island, has a large amount of kaolin deposit that being sold at low price. This price could be increased ten times when being sold as metakaolin. This study aimed to compare mechanical and metallurgical properties of commercial metakaolin and Bangka kaolin which calcinated at 700°C. Both metakaolins reacted with NaOH and waterglass as the activator followed by curing at room temperature for 7, 14 and 28 days and elevated temperature of 60°C for 4, 12 and 24 hours. Mechanical properties will be examined by compressive strength and flexural strength test, while the metallurgical properties will be evaluated with SEM, and TAM. The results of the mechanical test will be used to determine which geopolymer will perform well with the microstructure and thermal activity to support the finding. These attempts will be done in order to improve the properties of Bangka metakaolin geopolymer superior to commercial metakaolin.

Abstrak :
This book presents a comprehensive knowledge-set of matrix, fiber and interphase behavior under long-term aging conditions, theoretical modeling and experimental methods. This book covers long-term constituent behavior, predictive methodologies, experimental validation and design practice. Readers will also find a discussion of various applications, including aging air craft structures, aging civil infrastructure, in addition to engines and high temperature applications.

Abstrak :
This book, addresses the wide range of parameters that affect the interaction of fluids with polymers and polymeric composites. The book aims at broadening the scope of available data, mostly limited up to this time to weight-gain recordings of fluid ingress into polymers and composites, to the practical circumstances of fluctuating exposure. Various forms of experimental data are given, in conjunction with theoretical models derived from basic scientific principles, and correlated with severity of exposure conditions and interpreted by means of rationally based theoretical models. The practical implications of the effects of fluids are discussed. The issue of fluid effects on polymers and polymeric composites is of concern to engineers and scientists active in aerospace and naval structures, as an increasing portion of these structures are made of polymeric composites and employ polymeric adhesives as a joining device.

Abstrak :
Concerns about global warming and the depletion of oil reserves have led to significant research into more sustainable composite materials made from natural materials. Recently, research has focussed on the development of nanoscale reinforcements for this new group of composites, significantly improving and extending their range of desirable properties. Environmentally friendly polymer nanocomposites summarises this wealth of research and its practical implications. After an introduction to the subject, part one looks at matrix and reinforcement materials as well as their characterisation. Part two reviews key properties such as tensile and dynamic mechanical properties and thermal stability. It also considers issues such as barrier properties, biodegradability, rheology, electrical and thermal conductivity. The book concludes by reviewing potential applications.

Abstrak :
The increased use of polymer matrix composites in structural applications has led to the growing need for a very high level of quality control and testing of products to ensure and monitor performance over time. Non-destructive evaluation (NDE) of polymer matrix composites explores a range of NDE techniques and the use of these techniques in a variety of application areas. Part one provides an overview of a range of NDE and NDT techniques including eddy current testing, shearography, ultrasonics, acoustic emission, and dielectrics. Part two highlights the use of NDE techniques for adhesively bonded applications. Part three focuses on NDE techniques for aerospace applications including the evaluation of aerospace composites for impact damage and flaw characterisation. Finally, the use of traditional and emerging NDE techniques in civil and marine applications is explored in part four. With its distinguished editor and international team of expert contributors, Non-destructive evaluation (NDE) of polymer matrix composites is a technical resource for researchers and engineers using polymer matrix composites, professionals requiring an understanding of non-destructive evaluation techniques, and academics interested in this field.

Abstrak :
Penggunaan serat alami seperti serabut kelapa pada bahan semen memodifikasi sifat reologi dari bahan pada kondisi segar dan sifat mekanik pada kondisi keras. Sifat fisik dan kimia dapat mengubah interface antara serat dan matriks selama pengerasan. Pada penelitian ini dilakukan pengujian terhadap matriks dan serat yang digunakan. Kemudian dilakukan proses fabrikasi sampel. Langkah terakhir dipelajari pengaruh beban yang diterapkan pada matriks terhadap ikatan antara matriks dan serat. Hasil pengujian menunjukkan bahwa penambahan serabut dalam air yang digunakan dalam pasta menurunkan kekuatan matriks. Sedangkan adhesi antara makriks dengan serat meningkat seiring dengan meningkatnya konsolidasi matriks. ......The use of natural fibers such as coconut fiber in cementitious materials modifies the rheological properties of the fresh material and mechanical properties in the hardened state. Its physical and chemical properties can modify the interface between fiber and matrix during hardening. Initially the study and presentation of matrix and fiber used are provided. Then the process of samples fabrication is presented. In the last step, the influence of the load applied on the matrix to the adhesion between the matrix and fibers. Test results show that the addition of coir in the water used in the paste decreases the strength of matrix and the fiber-matrix adhesion increases with the growth of the matrix consolidation.